Willis Tower - wikipedia Willis Tower Willis Tower The Willis Tower, then known as the Sears Tower, in 1998 Willis Tower Location in Chicago Willis Tower Location in Illinois Willis Tower Location in the United States Show map of Chicago metropolitan area Show map of Illinois Show map of the US Show all Former names Sears Tower ( 1973 -- 2009 ) Record height Tallest in the world from 1973 to 1998 Preceded by World Trade Center ( 1970 ) Surpassed by Petronas Twin Towers General information Status Complete Type Office, observation, communication Architectural style International Location 233 S. Wacker Drive Chicago, Illinois 60606 United States Coordinates 41 ° 52 ′ 44 '' N 87 ° 38 ′ 09 '' W ﻿ / ﻿ 41.8789 ° N 87.6358 ° W ﻿ / 41.8789 ; - 87.6358 Coordinates : 41 ° 52 ′ 44 '' N 87 ° 38 ′ 09 '' W ﻿ / ﻿ 41.8789 ° N 87.6358 ° W ﻿ / 41.8789 ; - 87.6358 Current tenants United Airlines Named for Willis Group Sears ( 1973 -- 2009 ) Construction started 1970 ; 48 years ago ( 1970 ) Completed 1973 ; 45 years ago ( 1973 ) Owner Blackstone Group Height Architectural 442.1 m ( 1,450 ft ) Tip 527 m ( 1,729 ft ) Top floor 412.7 m ( 1,354 ft ) Technical details Floor count 108 ( + 3 basement floors ), 110 floors including mechanical. Floor area 416,000 m ( 4,477,800 sq ft ) Lifts / elevators 104, with 16 double - decker elevators, made by Westinghouse, modernized by Schindler Group Design and construction Architect Skidmore, Owings and Merrill Fazlur Rahman Khan Bruce Graham Main contractor Morse Diesel International References I. ^ Willis Tower at Emporis The Willis Tower, built as and still commonly referred to as the Sears Tower, is a 110 - story, 1,450 - foot ( 442.1 m ) skyscraper in Chicago, Illinois. At completion in 1973, it surpassed the World Trade Center towers in New York to become the tallest building in the world, a title it held for nearly 25 years ; it remained the tallest building in the Western Hemisphere until the completion of a new building at the World Trade Center site in 2014. The building is considered a seminal achievement for its designer Fazlur Rahman Khan. The Willis Tower is the second - tallest building in the United States and the Western hemisphere -- and the 16th - tallest in the world. More than one million people visit its observation deck each year, making it one of Chicago 's most - popular tourist destinations. The structure was renamed in 2009 by the Willis Group as part of its lease on a portion of the tower 's space. As of December 2013, the building 's largest tenant is United Airlines, which moved its corporate headquarters from the United Building at 77 West Wacker Drive in 2012 and today occupies around 20 floors with its headquarters and operations center. Contents 1 History 1.1 Planning and construction 1.2 Suits filed to halt construction 1.3 Post-opening 1.4 Plans 2 Skydeck 3 Height 3.1 Position in Chicago 's skyline 3.2 Climbing 4 Naming rights 5 Figures and statistics 6 Broadcasting 6.1 Radio stations 6.2 Television stations 7 Cultural depictions 7.1 Film and television 7.2 Other 8 Image gallery 9 See also 10 References 11 External links History Planning and construction Breakdown of the bundled tube structure of Willis Tower with simplified floor plans In 1969, Sears, Roebuck & Co. was the largest retailer in the world, with about 350,000 employees. Sears executives decided to consolidate the thousands of employees in offices distributed throughout the Chicago area into one building on the western edge of Chicago 's Loop. Sears asked its outside counsel, Arnstein, Gluck, Weitzenfeld & Minow ( now known as Arnstein & Lehr, LLP ) to suggest a location. The firm consulted with local and federal authorities and the applicable law, then offered Sears two options : the Goose Island area northwest of downtown, and a two - block area bounded by Franklin Street on the east, Jackson Boulevard on the south, Wacker Drive on the west and Adams Street on the north, with Quincy Street running through the middle from east to west. This latter site was decided upon, and preliminary inquiries determined that the necessary permits could be obtained and Quincy Street vacated. The next step was to acquire the property ; a team of attorneys from the Arnstein law firm, headed by Andrew Adsit, began buying the property parcel by parcel. Sears purchased 15 old buildings from 100 owners and paid $2.7 million to the City of Chicago for the portion of Quincy Street that divided the property. Sears, which needed 3,000,000 square feet ( 280,000 m ) of office space for its planned consolidation and predicted that growth would require yet more, commissioned architects Skidmore, Owings & Merrill ( SOM ) to produce a structure to be one of the largest office buildings in the world. Their team of architect Bruce Graham and structural engineer Fazlur Rahman Khan designed the building as nine square `` tubes '' ( each essentially a separate building ), clustered in a 3 × 3 matrix forming a square base with 225 - foot ( 69 m ) sides. All nine tubes would rise up to the 50th floor of the building. At the 50th floor, the northwest and southeast tubes end, and the remaining seven continue up. At the 66th floor, the northeast and the southwest tubes end. At the 90th floor, the north, east, and south tubes end. The remaining west and center tubes continue up to the 108th floor. The Sears Tower during its construction, in 1973 The Willis Tower was the first building to use Khan 's bundled tube structure. This innovative design was structurally efficient and economic : at 1,450 feet, it provided more space and rose higher than the Empire State Building, yet cost much less per unit area. This structural system would prove highly influential in skyscraper construction. It has been used in most supertall buildings since then, including the world 's tallest building, the Burj Khalifa. To honor Khan 's contributions, the Structural Engineers Association of Illinois commissioned a sculpture of him for the lobby of the Willis Tower. A sculpture honoring Fazlur Khan at the Willis Tower Sears executives decided that the space they would immediately occupy should be efficiently designed to house their Merchandise Group, and that floor space for future growth would be rented out to smaller firms and businesses until Sears could retake it. The latter floor areas had to be designed to a smaller plate, with a high window - space to floor - space ratio, to be attractive and marketable to prospective lessees. Smaller floorplates required a taller structure to yield sufficient square footage. Skidmore architects proposed a tower with large 55,000 - square - foot ( 5,100 m ) floors in the lower part of the building, and gradually tapered areas of floorplates in a series of setbacks, which would give the Sears Tower its distinctive look. As Sears continued to offer optimistic projections for growth, the tower 's proposed floor count rapidly increased into the low hundreds, surpassing the height of New York 's unfinished World Trade Center to become the world 's tallest building. The height was restricted by a limit imposed by the Federal Aviation Administration ( FAA ) to protect air traffic. The financing of the tower was provided by the Sears company. It was topped with two antennas to permit local television and radio broadcasts. Sears and the City of Chicago approved the design, and the first steel was put in place in April 1971. The structure was completed in May 1973. The construction cost about US $150 million at the time, equivalent to $830 million in 2018. By comparison, Taipei 101, built in 2004 in Taiwan, cost around the equivalent of US $2.21 billion in 2018 dollars. Black bands appear on the tower around the 29th -- 32nd, 64th -- 65th, 88th -- 89th, and 104th -- 108th floors. These are louvres that allow ventilation for service equipment and obscure the structure 's belt trusses. Even though regulations did not require a fire sprinkler system, the building was equipped with one from the beginning. There are around 40,000 sprinkler heads in the building, installed at a cost of $4 million. In February 1982, two television antennas were added to the structure, increasing its total height to 1,707 feet ( 520.3 m ). The western antenna was later extended, bringing the overall height to 1,729 feet ( 527 m ) on June 5, 2000, to improve reception of local NBC station WMAQ - TV. Suits filed to halt construction As the construction of the building neared the 50th floor, lawsuits for an injunction were filed seeking to stop the building from exceeding 67 floors. The suits alleged that above that point television reception would deteriorate and cause property values to plummet. The first suit was filed by the State 's Attorney in neighboring Lake County on March 17, 1972. A second suit was filed on March 28 in the Cook County Circuit Court by the Villages of Skokie, Northbrook and Deerfield, Illinois. Sears filed motions to dismiss the Lake County and the Cook County lawsuits and on May 17, 1972, Judge LaVerne Dickson, Chief of the Lake County Circuit Court dismissed the suit, saying, `` I find nothing that gives television viewers the right to reception without interference. They will have to find some other means of ensuring reception such as taller antennas. '' The Lake County State 's Attorney filed a Notice of Appeal and the Supreme Court agreed to permit bypassing the appellate court and to hear the matter on an expedited basis. The State 's Attorney then asked the Illinois Supreme Court for a temporary injunction to stop the construction and his request was denied. On June 12, Judge Charles R. Barrett granted Sears ' motion to dismiss the suit filed by the three Chicago suburbs on the grounds that interference with television reception caused by construction of the Sears building did not violate constitutional rights and that the suburbs involved in the suit do not have any right to undistorted television reception. This decision was also appealed and consolidated with the Lake County appeal with the Supreme Court of Illinois. Meanwhile, an Illinois Citizens ' Committee for Broadcasting requested the Federal Communications Commission to halt construction so that the building would not interfere with area television reception. On May 26, 1972, the Commission declined to take action on the grounds that it did not have jurisdiction to do so. On June 30, 1972, the Illinois Supreme Court affirmed the previous rulings by Lake and Cook County Circuit Courts, by a letter order with a written opinion to follow. On September 8, 1972, the United States Court of Appeals for the Seventh Circuit upheld the decision by the Federal Communications Commission to dismiss the complaint brought by the Illinois Citizens Committee for Broadcasting charging that the building would drastically affect reception in the Chicago market and requesting the FCC to halt construction. The Supreme Court of Illinois written opinion was filed on September 20, 1972. In affirming the judgments of lower courts the Court held, `` Considering the foregoing, it is clear to us that absent legislation to the contrary defendant has a propriety right to construct a building to its desired height and that completion of the project would not constitute a nuisance under the circumstances of this case. '' Post-opening Willis Tower at dusk, seen from the Loop Willis Tower from across the Chicago River Sears ' optimistic growth projections were not met. Competition from its traditional rivals ( like Montgomery Ward ) continued, with new competition by retailing giants such as Kmart, Kohl 's, and Walmart. The fortunes of Sears & Roebuck declined in the 1970s as the company lost market share ; its management grew more cautious. Nor did the Sears Tower draw as many tenants as Sears had hoped. The tower stood half - vacant for a decade as a surplus of office space was erected in Chicago in the 1980s. In 1990, the law firm of Keck, Mahin & Cate decided to move out of its space in the Sears Tower and into a development that would become 77 West Wacker Drive, rebuffing Sears ' attempts to entice the firm to stay. Two years later, Sears began moving its own offices out of the Sears Tower. In 1994, Sears sold the building to Boston - based AEW Capital Management, with financing from MetLife. At the time, it was one - third vacant. By 1995, Sears had completely left the building, moving to a new office campus in Hoffman Estates, Illinois. In 1997, Toronto - based TrizecHahn Corporation ( the owner of the CN Tower at the time ) purchased the building for $110 million, and assumption of $4 million in liabilities, and a $734 million mortgage. In 2003, Trizec surrendered the building to lender MetLife. In 2004, MetLife sold the building to a group of investors, including New York - based Joseph Chetrit, Joseph Moinian, Lloyd Goldman, Joseph Cayre and Jeffrey Feil, and Skokie, Illinois - based American Landmark Properties. The quoted price was $840 million, with $825 million held in a mortgage. In June 2006, seven men were arrested by the FBI and charged with plotting to destroy the tower. Deputy FBI Director John Pistole described their plot as `` more aspirational than operational ''. The case went to court in October 2007 ; after three trials, five of the suspects were convicted and two were acquitted. The alleged leader of the group, Narseal Batiste, was sentenced to 131⁄2 years in prison in November 2009. Plans In February 2009, the owners announced they were considering a plan to paint the structure silver ; this plan was later dropped. The paint would have `` rebranded '' the building and highlighted its advances in energy efficiency. The estimated cost was $50 million. Since 2007, the building owners have been considering building a hotel on the north side of Jackson, between Wacker and Franklin, at the plaza that is the entrance to the tower 's observation deck. The tower 's parking garage is beneath the plaza. Building owners say the second building was considered in the original design. The plan was eventually cancelled as city zoning does not permit construction of such a tall tower there. Although Sears ' naming rights expired in 2003, the building continued to be called the Sears Tower for several years. In March 2009, London - based insurance broker Willis Group Holdings agreed to lease a portion of the building, and obtained the building 's naming rights. On July 16, 2009, the building was officially renamed Willis Tower. On August 13, 2012, United Airlines announced it would move its corporate headquarters from 77 West Wacker Drive to Willis Tower. In 2015, the Blackstone Group completed purchase of the tower for a reported $1.3 billion, the highest price ever paid for a U.S. property outside New York City. The new owners are considering several plans for further site developments. Skydeck The Willis Tower observation deck, called the Skydeck, opened on June 22, 1974. Located on the tower 's 103rd floor, it is 1,353 feet ( 412.4 m ) high, making it the highest observation deck in the United States and one of Chicago 's most famous tourist attractions. Tourists can experience how the building sways on a windy day. They also can see far over the plains of Illinois and across Lake Michigan to Indiana, Michigan, and Wisconsin on a clear day. Elevators take tourists to the top in about 60 seconds, and allow tourists to feel the pressure change as they rise up. The Skydeck competes with the John Hancock Center 's observation floor a mile and a half away, which is 323 feet ( 98.5 m ) lower. Some 1.7 million tourists visit the Skydeck annually. A second Skydeck on the 99th floor is also used if the 103rd floor is closed. The tourist entrance can be found on the south side of the building along Jackson Boulevard. In January 2009, Willis Tower 's owners began a major renovation of the Skydeck, including the installation of retractable glass balconies, which can be extended approximately 4 feet ( 1.2 m ) from the facade of the 103rd floor, overlooking South Wacker Drive. The all - glass boxes, informally dubbed `` The Ledge '', allow visitors to look through the glass floor to the street 1,353 feet ( 412 m ) below. The boxes, which can bear 5 short tons ( 4.5 metric tons ) of weight, opened to the public on July 2, 2009. On May 29, 2014, the laminated glass covering the floor of one of the glass boxes shattered while visitors were sitting on it, but caused no injuries. The broken glass was replaced within days, and tourist operations resumed as before. Three glass bottom skyboxes ( top right ) on the west façade of Willis Tower at the 103rd floor View looking down from glass balcony Glass balcony at the skydeck Panorama of Chicago skyline as seen from Willis Tower Skydeck Sunset on Chicago Skyline view from the Skydeck Height Height comparison of Willis Tower with other tall structures. From left to right : Burj Khalifa, Dubai ; CN Tower, Toronto ; Willis Tower, Chicago The Willis Tower remains the second tallest building in the Americas ( after One World Trade Center ) and the Western Hemisphere. With a pinnacle height of 1,729 feet ( 527 m ), it is the third - tallest freestanding structure in the Americas, as it is 86 feet ( 26.2 m ) shorter than Toronto 's CN Tower. Willis Tower is the eighth - tallest freestanding structure in the world by pinnacle height. At 1,482.6 feet ( 451.9 m ) tall, including decorative spires, the Petronas Twin Towers in Kuala Lumpur, Malaysia, laid claim to replacing the Sears Tower as the tallest building in the world in 1998. Not everyone agreed, and in the ensuing controversy, four different categories of `` tallest building '' were created. Of these, Petronas was the tallest in the first category ( height to top of architectural elements, meaning spires but not antennas ), giving it the title of world 's tallest building. Taipei 101 in Taiwan claimed the record in three of the four categories in 2004 to become recognized as the tallest building in the world. Taipei 101 surpassed the Petronas Twin Towers in spire height and the Sears Tower in roof height and highest occupied floor. The Sears Tower retained one record : its antenna exceeded Taipei 101 's spire in height. In 2008, the Shanghai World Financial Center claimed the records of tallest building by roof and highest occupied floor. On August 12, 2007, the Burj Khalifa in Dubai, United Arab Emirates was reported by its developers to have surpassed the Sears Tower in all height categories. Upon completion, One World Trade Center in New York City surpassed the Willis Tower through its structural and pinnacle heights, but not by roof, observation deck elevation, or highest occupied floor. Until 2000, the Sears Tower did not hold the record for being the tallest building by pinnacle height. From 1969 to 1978, this record was held by the John Hancock Center, whose antenna reached a height of 1,500 feet ( 457.2 m ), or 49 feet ( 14.9 m ) taller than the Sears Tower 's original height of 1,450 feet ( 442.1 m ). In 1978, One World Trade Center became taller by pinnacle height due to the addition of a 359 feet ( 109.4 m ) antenna, which brought its total height to 1,727 feet ( 526.4 m ). In 1982, two antennas were installed on top of the Sears Tower which brought its total height to 1,707 feet ( 520.3 m ), making it taller than the John Hancock Center but not One World Trade Center. However, the extension of the Sears Tower 's western antenna in June 2000 to 1,729 feet ( 527 m ) allowed it to just barely claim the title of tallest building by pinnacle height. Position in Chicago 's skyline Climbing On May 25, 1981, Dan Goodwin, wearing a homemade Spider - Man suit while using suction cups, camming devices, and sky hooks, and despite several attempts by the Chicago Fire Department to stop him, made the first successful outside ascent of the Sears Tower. Goodwin was arrested at the top after the seven - hour climb, and he was later charged with trespassing. Goodwin stated that the reason he made the climb was to call attention to shortcomings in high - rise rescue and firefighting techniques. After a lengthy interrogation by Chicago 's District Attorney and Fire Commissioner, Goodwin was officially released from prison. In August 1999, French urban climber Alain `` Spiderman '' Robert, using only his bare hands and bare feet, scaled the building 's exterior glass and steel wall all the way to the top. A thick fog settled in near the end of his climb, making the last 20 stories of the building 's glass and steel exterior slippery. Naming rights West facade and entrance Although Sears sold the Tower in 1994 and had completely vacated it by 1995, the company retained the naming rights to the building through 2003. The new owners were rebuffed in renaming deals with CDW Corp in 2005 and the U.S. Olympic Committee in 2008. London - based insurance broker Willis Group Holdings, Ltd. leased more than 140,000 square feet ( 13,000 m ) of space on three floors in 2009. A Willis spokesman said the naming rights were obtained as part of the negotiations at no cost to Willis, and the building was renamed Willis Tower on July 16, 2009. The naming rights are valid for 15 years, so it is possible that the building 's name could change again in 2024 or later. The Chicago Tribune joked that the building 's new name reminded them of the oft - repeated `` What you talkin ' ' bout, Willis ? '' catchphrase from the 1980s American television sitcom Diff'rent Strokes and considered the name - change ill - advised in `` a city with a deep appreciation of tradition and a healthy ego, where some Chicagoans still mourn the switch from Marshall Field 's to Macy 's ''. This feeling was confirmed in a July 16, 2009 CNN article in which some Chicago area residents expressed reluctance to accept the Willis Tower name, and in an article that appeared in the October 2010 issue of Chicago magazine that ranked the building among Chicago 's 40 most important, the author pointedly refused to acknowledge the name change and referred to the building as the `` Sears Tower ''. Time magazine called the name change one of the top 10 worst corporate name changes and pointed to negative press coverage by local news outlets and online petitions from angry residents. The naming rights issue continued into 2013, when Eric Zorn noted in the Chicago Tribune that `` We 're stubborn about such things. This month marked four years since the former Sears Tower was re-christened Willis Tower, and the new name has yet to stick. '' Figures and statistics The top of Willis Tower is the highest point in Illinois. The tip of its highest antenna is 1,729 feet ( 527 m ) above street level or 2,325 feet ( 708.7 m ) above sea level, its roof is 1,450 feet 7 inches ( 442.14 m ) above street level or 2,046 feet ( 623.6 m ) above sea level, the 103rd floor observation deck ( The Sky deck ) is 1,353 feet ( 412 m ) above street level or 1,948 feet ( 593.8 m ) above sea level, the Franklin Street entrance is 595 feet ( 181.4 m ) above sea level. ( The highest natural point in Illinois is the Charles Mound, at 1,235 feet ( 376.4 m ) above sea level. ) The building leans about 4 inches ( 10.2 cm ) towards the west due to its slightly asymmetrical design, placing unequal loads on its foundation. The design for Willis Tower incorporates nine steel - unit square tubes in a 3 tube by 3 tube arrangement, with each tube having the footprint of 75 ft × 75 ft ( 22.9 m × 22.9 m ). Willis Tower was the first building for which this design was used. The design allows future growth of extra height to the tower if wanted or needed. The restrooms on the 103rd floor, at 1,353 feet ( 412.4 m ) high, are the highest ( relative to street level ) in the Western Hemisphere. The design was inspired by an advertisement for a package of cigarettes. The Franklin Street entrance is the point from which all building heights are measured. The Wacker Drive entrance is six feet higher than the Franklin Street entrance, lower Wacker Drive / Lower Level 1 is approximately 17 feet, 6 inches lower than the Wacker Drive entrance and 11 feet, six inches lower than Franklin Street. The 103rd floor observation deck is 1,354 feet above the Franklin Street entrance. The glass ledges in the Skydeck are on a raised platform 18 inches higher than the rest of the 103rd floor or 1,349 feet, six inches above the Wacker Drive entrance, 1,355 feet, six inches above the Franklin Street entrance and 1,367 feet above lower Wacker Drive / Lower Level 1. The Skydeck elevators rise from Lower Level 2 which gives a total rise of approximately 1,382 feet to the 103rd floor. The building 's total building area stands at 351,846 m ( 3,787,200 sq ft ) It remains the world 's tallest steel - construction building. All taller buildings use concrete or composite construction. Broadcasting Many broadcast station transmitters are located at the top of Willis Tower. Each list is ranked by height from the top down. Stations at the same height on the same mast indicate the use of a diplexer into the same shared antenna. Due to its extreme height, FM stations ( all class B) are very limited in power output. Radio Stations East mast 482 m : WLIT FM 93.9 MHz main, 4.0 kW, AMFM WEBG FM 95.5 backup, 3.1 kW, AMFM 480 m : WBMX FM 104.3 main, 4.1 kW, CBS Radio 476 m : WTMX FM 101.9 main, 4.2 kW, Hubbard 474 m : WBBM FM 96.3 main, 4.2 kW, CBS Radio 472 m : WKSC FM 103.5 main, 4.3 kW, AMFM WGCI FM 107.5 main, 3.7 kW, AMFM 470 m : WFMT FM 98.7, 6.0 kW 468 m : WLS FM 94.7 main, 4.4 kW FCC query West mast 460 & 451 m : WFMT FM 98.7 backups 443 m : WBBM - FM 96.3 backup WBMX 104.3 backup unknown : W264BF 100.7 MHz, 2 W, Calvary Chapel of Costa Mesa table of allotments : * * WLIT, WLS, WBBM, WTMX, WBMX, WCFS FCC query Also, NOAA Weather Radio station KWO39 transmits off the top of Willis Tower, at 162.550 MHz. KWO39, programmed by the National Weather Service Weather Forecast Office in Chicago, is equipped with Specific Area Message Encoding ( SAME ), which sets off a siren on specially - programmed weather radios to alert of an impending hazard, such as a tornado or civil emergency. Television Stations East mast 515 m : WLS - TV 7 analog, 55 kW, ABC Owned Television Stations ( Analog Broadcast discontinued as of June 12, 2009. Now broadcasting only in digital. ) WLS - TV 7 permanent digital, 4.75 kW 510 m : WCPX - TV 43 digital, 200 kW, Ion Media Networks WCPX - TV 38 analog, 3630 kW, Ion Media Networks ( Analog Broadcast discontinued as of June 12, 2009. Now broadcasting only in digital. ) WJYS TV 36 digital, 145 kW, Oxford Media Group WCIU - TV 27 digital, 15.1 kW, Weigel Broadcasting 509 m : WXFT - TV 59 temporary digital, 200 kW, Univision Communications WXFT - TV 50 permanent digital, 230 kW, Univision Communications 498 m : WTTW TV 11 analog, 60.3 kW, Window To the World Communications ( Analog Broadcast discontinued as of June 12, 2009. Now broadcasting only in digital. ) WBBM - TV 12 digital, 8 kW, CBS Television Stations 480 m : WFLD TV 31 digital backup, 475 kW, Fox Television Stations WPWR - TV 51 digital backup, 508 kW, Fox Television Stations 478 m : WGN - TV 19 digital backup, 310 / 229 kW, Tribune Broadcasting 474 m : WTTW TV 47 digital backup, 150 kW, Window To the World Communications WLS - TV 52 digital backup, 220 kW, ABC Owned Television Stations unknown : WESV - LD 40 digital, 37.2 kW, Trinity Christian Center of Santa Ana FCC query West mast 523 m : WPWR - TV 51 digital, 1000 kW, Fox Television Stations 514 m, WLS - TV 52 temporary digital, 153.6 kW, ABC Owned Television Stations 508 m, WMAQ - TV 29 digital, 350 kW, NBC Owned Television Stations 494 m : WMAQ - TV 5 analog, 20 kW ( Analog Broadcast discontinued as of June 12, 2009. Now broadcasting only in digital. ) WPWR - TV 50 analog, 5000 kW ( Analog Broadcast discontinued as of June 12, 2009. Now broadcasting only in digital. ) WXFT - TV 60 analog, 5000 kW, ( Analog Broadcast discontinued as of June 12, 2009. Now broadcasting only in digital. ) 475 m : WFLD TV 31 digital, 690 / 1000 kW, Fox Television Stations 473 m : WCIU - TV 26 analog, 5000 kW ( Analog Broadcast discontinued as of June 12, 2009. Now broadcasting only in digital. ) 472 m : WCIU - TV 27 digital, 590 kW, Weigel Broadcasting WSNS - TV 44 analog 5000 kW, NBC Owned Television Stations ( Analog Broadcast discontinued as of June 12, 2009. Now broadcasting only in digital. ) WSNS - TV 45 digital 467 / 665 kW, NBC Owned Television Stations 465 m : WTTW TV 47 digital, 300 kW, Window To the World Communications 455 m : WJYS TV 36 digital, 50 kW, Oxford Media Group 453 m : WGN - TV 19 digital, 645 kW, Tribune Broadcasting unknown : WWME - CD 39 digital, 4.4 kW, Weigel Broadcasting WEDE - CD 34 digital, 50 kW, First United WMEU - CA 48 analog STA, 150 kW, Weigel Broadcasting WMEU - LD 32 digital, 15 kW FCC query Cultural depictions Willis Tower as viewed from Chicago 's Chinatown Film and television The building has appeared in numerous films and television shows set in Chicago such as Ferris Bueller 's Day Off, where Ferris and company watch the streets of Chicago from the observation deck. The television show Late Night with Conan O'Brien introduced a character called The Sears Tower Dressed In Sears Clothing when the show visited Chicago in 2006. The building is also featured in History Channel 's Life After People, in which it and other human - made landmarks suffer from neglect without humans around, and it collapses two hundred years after people are gone. In an episode of the television series Monk, Adrian Monk tries to conquer his fear of heights by imagining that he is on top of the Sears Tower. Also, in an episode of Kenan and Kel, Kenan Rockmore and Kel Kimble decide to climb to the top of the Sears Tower, so that Kenan can declare his love for a girl. In the movie Category 6 : Day of Destruction, the tower is damaged by a tornado. In `` 1969 '', a Season 2 episode of the science - fiction series Stargate SG - 1, the SG - 1 team accidentally travels back in time to the titular year. At one point, the team travels though Chicago and the Sears Tower is shown ( erroneously, since construction did not begin on the tower until two years later in 1971 ). In the 2004 film I, Robot, the tower is shown updated in the year 2035 with new triangular antennas. The tower is shown surpassed in height by the USR ( United States Robotics ) Building. In the 2008 film The Dark Knight, the tower is part of Gotham City. In the 2011 film Transformers : Dark of the Moon, the tower is featured in a number of scenes. The most notable one is when the N.E.S.T team tries to enter the city using V - 22 Osprey helicopters. They use Willis Tower for cover before using wing suits to descend into the city streets. In the movie, the tower is shown to be severely damaged by the Decepticon invasion of the city. In the 2013 film Man of Steel, the tower 's interior and parts of its exterior portrayed the offices of the Daily Planet. In the 2014 film Divergent, the tower is shown abandoned and decayed in a future Chicago. In the 2015 film Jupiter Ascending, the tower is featured prominently as the place where Caine and Jupiter await a spaceship to lift them off the planet. In the 2018 film Rampage, the Energyne corporation is headquartered in the building, and uses tower 's antenna to broadcast an echolocation signal that would bring three mutated monsters to town. After the antenna is destroyed by the beasts, the entire building topples to the ground. Other Older versions of Microsoft Flight Simulator would begin with the player on the runway of Meigs Field, facing a virtual version of the tower. In Sufjan Stevens ' 2005 album Illinois, the tower is referenced in the track `` Seer 's Tower '', whose title is a play on the tower 's now - former name, Sears Tower. Image gallery Sears Tower in 2007 Willis Tower as seen from John Hancock Center observation deck 900 North Michigan, Park Tower, the John Hancock Center, the Trump Tower, and Aon Center ( L-R ) as seen from Willis Tower Skydeck. Westward view from Willis Tower View down to South Wacker Drive from the Skydeck A view of Willis Tower at dusk A ground - level view of the multiple balconies at Willis Tower Skydeck View of Willis Tower from John Hancock Center The Eisenhower Espressway and Jane Byrne Interchange ( looking west from Willis Tower ) View of Lake Michigan from Willis Tower See also Chicago portal Illinois portal Architecture portal Architecture of Chicago List of buildings with 100 floors or more List of tallest buildings and structures in the world List of tallest buildings by U.S. state List of tallest buildings in Chicago List of tallest buildings in the United States List of tallest freestanding structures in the world List of tallest towers in the world Sears, Roebuck and Company Complex References Jump up ^ de la Merced, Michael J. ( March 16, 2014 ). `` Blackstone Group Purchases Landmark Willis Tower in Chicago ''. The New York Times. Retrieved August 11, 2015. ^ Jump up to : `` Willis Tower -- The Skyscraper Center ''. Council on Tall Buildings and Urban Habitat. June 13, 2015. Retrieved June 13, 2015. ^ Jump up to : The tower has 108 stories as counted by standard methods, though the building 's owners count the main roof as 109 and the mechanical penthouse roof as 110. Emporis.com Retrieved on June 7, 2008 Jump up ^ `` History and Facts - Willis Tower ''. willistower.com. Jump up ^ `` Five things you need to know about pioneering architect Fazlur Rahman Khan ''. The Independent. London. April 3, 2017. ^ Jump up to : ( 1 ) Archived August 15, 2012, at the Wayback Machine. Jump up ^ Snyder, Brett ( December 16, 2013 ). `` A Day with United Management : Elite Status, Mileage Devaluation, and Increasing Change Fees ''. The Cranky Flier. Retrieved December 18, 2013. Jump up ^ Kerch, Steve ( October 20, 1991 ). `` This job is a tall order : Sears Tower project is the height of redevelopment. '' Chicago Tribune. Jump up ^ Arnstein & Lehr, The First 120 Years Jump up ^ Chicago Tribune, December 28, 2003. Jump up ^ Chicago Tribune, January 4, 1971. Jump up ^ `` The Tallest Skyscraper '', Time, June 11, 1973 Jump up ^ Richard G. Weingardt ( 2005 ). Engineering Legends : Great American Civil Engineers. American Society of Civil Engineers. p. 75. ISBN 978 - 0 - 7844 - 7121 - 0. Jump up ^ National Academy of Engineering ( 1979 ). Memorial Tributes. National Academies. NAP : 14723. Jump up ^ `` Burj Dubai : The new pinnacle of vanity ''. Telegraph. Retrieved February 25, 2014. Jump up ^ `` Top 10 world 's tallest steel buildings ''. Constructionweekonline.com. Retrieved February 25, 2014. Jump up ^ `` Fazlur Khan Sculpture ''. SEAOI. Retrieved February 25, 2014. Jump up ^ `` Databank : Sears Tower '', Wonders of the World, PBS Databank. Retrieved November 19, 2007. Jump up ^ Federal Reserve Bank of Minneapolis Community Development Project. `` Consumer Price Index ( estimate ) 1800 -- ''. Federal Reserve Bank of Minneapolis. Retrieved January 2, 2018. Jump up ^ `` Inflation Calculator -- Find US Dollar 's Value from 1913 -- 2015 ''. US Inflation Calculator. Jump up ^ The Times - News, February 15, 1975 Jump up ^ Chicago Tribune, April 9, 1972 and Chicago Tribune, May 7, 1972. Jump up ^ Chicago Tribune, May 18, 1972. Jump up ^ Chicago Tribune, June 10, 1972. Jump up ^ Chicago Tribune, June 13, 1972. Jump up ^ Chicago Tribune, July 1, 1972. Jump up ^ Chicago Tribune, September 12, 1972 ; Illinois Citizens Committee for Broadcasting v. Federal Communications Commission, 467 F. 2d 1397 ( 7th Cir. 1972 ). Jump up ^ Peo. Ex Rel. Hoogasiam v. Sears Robebuck, Ill. 52 L. 2d 301 ( 1972 ). Jump up ^ For information on this transformation, see Donald R. Katz The Big Store : Inside the Crisis and Revolution at Sears, New York ( Viking ), 1987. Jump up ^ `` 77 W. Wacker ready to go. '' Chicago Sun - Times. March 12, 1990. Retrieved on November 12, 2009. Jump up ^ `` Sears Picks Hoffman Estates ''. tribunedigital - chicagotribune. Retrieved 2018 - 02 - 09. Jump up ^ Cliff Edwards, Associated Press. `` TrizecHahn buys control of Chicago 's Sears Tower World 's 2d - tallest building sold for $110 m '', The Boston Globe, December 4, 1997. Retrieved February 25, 2009 from HighBeam Research Jump up ^ `` Sears Tower may be for sale '', Crains Chicago Business, October 31, 1997 Jump up ^ `` Trizec to sell its last local asset '', Crain 's Chicago Business, September 27, 2006 Jump up ^ `` BIZ BRIEFS '', Chicago Sun - Times, May 1, 2004. Retrieved February 25, 2009 from HighBeam Research Jump up ^ `` MetLife to Complete Sale of Chicago 's Sears Tower '', Chicago Tribune ( Chicago, IL ), April 30, 2004. Retrieved February 25, 2009 from HighBeam Research Jump up ^ `` FBI Killed Plot in Talking Stage ''. New York Times, June 24, 2006. Jump up ^ `` Seven charged over ' Chicago plot ' ''. BBC News, June 23, 2006. Jump up ^ `` Sears Tower ' plot trial ' begins '', BBC News, October 3, 2007. Jump up ^ `` Five guilty in Chicago bomb plot '', BBC News, May 12, 2009. Jump up ^ `` Sears Tower bomb plot leader Narseal Batiste jailed '', BBC News, November 20, 2009. Jump up ^ `` Sears Tower in silver ? '', Chicago Sun - Times, February 25, 2009 Archived February 17, 2010, at the Wayback Machine. Jump up ^ David Roeder. `` Tall order for Tower ? ; Sears Tower owners to press city for zoning change, subsidy to add 2nd building as part of mega-million - dollar project next to landmark '', Chicago Sun - Times, October 12, 2007. Retrieved February 25, 2009 from HighBeam Research Jump up ^ `` Sears Tower Being Renamed ''. Chicago Breaking News. March 12, 2009 Jump up ^ `` Tallest Building in Western Hemisphere is Renamed Willis Tower '' ( Press release ). Willis Group. July 16, 2009. Retrieved June 13, 2015. Jump up ^ `` Subscription Center ''. Jump up ^ `` Sears Tower unveils 103rd floor glass balconies '', USA Today, July 1, 2009 Jump up ^ `` The Ledge at Skydeck Chicago ''. Archived from the original on June 8, 2011. Retrieved May 15, 2011. SOM.com Project Page Jump up ^ BJ Lutz ( May 30, 2014 ). `` Coating on Willis Tower Skydeck 's Ledge Cracks Under Tourists ''. Nbcchicago.com. Retrieved August 26, 2014. Jump up ^ `` Height : The History of Measuring Tall Buildings ''. Council on Tall Buildings and Urban Habitat. Retrieved May 1, 2012. Jump up ^ `` Burj Khalifa surpasses the height of Sears Tower in Chicago ''. Visitdubai.info. December 9, 2007. Retrieved October 31, 2011. Jump up ^ `` Freedom Tower ( '' World Trade Center 1 `` ) ''. NYC Tower. Archived from the original on December 21, 2008. Retrieved November 30, 2008. Jump up ^ `` Chicago Cubs History and News -- Welcome to Just One Bad Century ''. Justonebadcentury.com. Archived from the original on March 20, 2012. Retrieved October 31, 2011. Jump up ^ `` Sears Tower in Chicago Is Scaled by Stunt Man ''. Chicago ( Ill ) : New York Times. May 26, 1981. Retrieved October 31, 2011. Jump up ^ `` Spiderman scales Sears Tower w / Stan Lee interview ''. YouTube. Retrieved January 13, 2009. Jump up ^ `` ' Spiderman ' scales Sears Tower in Chicago -- August 20, 1999 ''. CNN. Retrieved September 14, 2009. Jump up ^ `` Sears Tower name to change to Willis Tower ''. Chicago Tribune. March 12, 2009. Archived from the original on April 19, 2009. Retrieved May 1, 2009. Jump up ^ `` Sears Tower Now Willis ''. Chicago Tribune. July 16, 2009. Retrieved July 16, 2009. Jump up ^ Corfman, Thomas A. ( March 11, 2009 ). `` Willis could get Sears Tower naming rights ''. Chicago Real Estate Daily. Retrieved October 31, 2011. ^ Jump up to : Podmolik, Mary Ellen ( July 16, 2009 ). `` Sears Tower name change : Building today officially becomes Willis Tower ''. Chicago Tribune. Retrieved July 16, 2009. Jump up ^ Burns, Greg ( July 16, 2009 ). `` Burns on Business, Willis Wants to be Part of Chicago by Way of Jersey ''. Chicago Tribune. Retrieved July 16, 2009. Jump up ^ Podmolik, Mary Ellen ( 2009 ). `` Sears Tower name change has few Chicago fans -- Willis Tower may have trouble winning over public ''. Chicago Tribune. The Tribune Company ( March 13, 2009 ). Jump up ^ `` Sears Tower Now Named Willis Tower ''. CNN. July 16, 2009. Retrieved July 17, 2009. Jump up ^ Johnson, Geoffrey ( 2010 ). `` Top 40 Buildings in Chicago ''. Chicago. The Tribune Company ( October 2010 ). Jump up ^ Suddath, Claire ( February 8, 2010 ). `` Top 10 Worst Corporate Name Changes : It 's the Sears Tower ''. TIME. Retrieved February 8, 2010. Jump up ^ Zorn, Eric ( 2013 ). `` Change of Subject -- ' Thillens Stadium ' is no more ''. Chicago Tribune. The Tribune Company ( June 24, 2013 ). Jump up ^ `` Sears Tower ''. Tallest Building in the World. September 2, 2007. Retrieved September 14, 2009. Jump up ^ `` Why Was the Sears Tower Built ? ''. Whyguides.com. June 5, 2000. Retrieved October 31, 2011. Jump up ^ The History Channel ; Modern Marvels ( series ) ; episode : The Sears Tower Jump up ^ `` CrediFi ''. Sears Tower. Retrieved September 19, 2016. Jump up ^ `` 100 Tallest Completed Buildings in the World ''. Council on Tall Buildings & Urban Habitat. Retrieved 4 October 2017. Jump up ^ `` FM Query Results -- Audio Division ( FCC ) USA ''. Fcc.gov. Retrieved September 7, 2016. Jump up ^ `` FM Query Results -- Audio Division ( FCC ) USA ''. Fcc.gov. Retrieved September 7, 2016. Jump up ^ `` TV Query Results -- Video Division ( FCC ) USA ''. Fcc.gov. Retrieved September 7, 2016. Jump up ^ `` TV Query Results -- Video Division ( FCC ) USA ''. Fcc.gov. Retrieved September 7, 2016. Jump up ^ `` Filming Locations for Ferris Bueller 's Day Off ''. Movie-locations.com. Retrieved September 14, 2009. Jump up ^ `` The Sears Tower Dressed In Sears Clothing ''. Nbc5.com. Archived from the original on March 2, 2008. Retrieved October 31, 2011. Jump up ^ Keith Darcé ( January 31, 2007 ). `` Madison Avenue turns to Main Street The San Diego Union - Tribune ''. Signonsandiego.com. Retrieved September 14, 2009. Jump up ^ Merrion, Paul ( September 7, 2011 ). `` Willis Tower, CBOT Building star in Superman filming ''. ChicagoBusiness. Retrieved July 26, 2013. External links Wikimedia Commons has media related to Willis Tower. Official website Willis Tower office - space leasing website Willis Tower Skydeck website Willis Tower on CTBUH Skyscraper Center Willis Tower at Structurae `` Willis Tower ''. Phorio. Records Preceded by One World Trade Center ( 1970 ) Tallest building in the world 442 m 1973 -- 1998 Succeeded by Petronas Towers World 's tallest building architectural element 442 m 1973 -- 1998 Building with the most floors 108 floors 2001 -- 2007 Succeeded by Burj Khalifa World 's tallest building rooftop 442 m 1973 -- 2003 Succeeded by Taipei 101 Tallest building in the United States 442 m 1973 -- 2013 Succeeded by One World Trade Center ( 2006 ) Preceded by Aon Center Tallest building in Chicago 442 m 1973 -- present Incumbent Chicago articles By topic Architecture Beaches Climate Colleges and universities Community areas Crime Culture Demographics Economy companies Expressways Flag Geography Government Harbor History Politics Timeline Landmarks Literature Media Museums Neighborhoods Parks People Performing arts music theater Public schools list Skyscrapers Sports Tourism Transportation Visual arts Portal Portal Tallest buildings by U.S. state AL RSA Battle House Tower AK Conoco - Phillips Building AZ Chase Tower AR Simmons Tower CA Wilshire Grand Center CO Republic Plaza CT City Place I DE River Tower at Christina Landing FL Panorama Tower GA Bank of America Plaza HI First Hawaiian Center ID Eighth and Main IL Willis Tower IN Salesforce Tower IA 801 Grand / Principal Building KS Epic Center KY 400 West Market LA One Shell Square ME Agora Grand Event Center MD Transamerica Tower MA John Hancock Tower MI Renaissance Center MN IDS Center MS Beau Rivage Hotel Casino MO One Kansas City Place MT First Interstate Center NE First National Bank Tower NV The Palazzo NH Manchester City Hall Plaza NJ 30 Hudson Street NM Albuquerque Plaza NY One World Trade Center NC Bank of America Corporate Center ND North Dakota State Capitol OH Key Tower OK Devon Energy Center OR Wells Fargo Center PA Comcast Technology Center RI Industrial National Bank Building SC Capital Center SD CenturyLink Tower TN AT&T Building TX JPMorgan Chase Tower UT Wells Fargo Center VT Decker Towers VA Westin Virginia Beach Town Center WA Columbia Center WV West Virginia State Capitol WI U.S. Bank Center WY White Hall DC Basilica of the Nat'l Shrine of the Immaculate Conception Supertall skyscrapers Current North America 432 Park Avenue 875 North Michigan Avenue Aon Center Bank of America Plaza Bank of America Tower Chrysler Building Empire State Building Franklin Center JPMorgan Chase Tower One World Trade Center One57 Salesforce Tower The New York Times Building Trump International Hotel and Tower Two Prudential Plaza U.S. Bank Tower Wells Fargo Plaza Willis Tower Wilshire Grand Center South America Gran Torre Santiago Asia China 85 Sky Tower Bank of China Tower Central Plaza The Center Chang Fu Jin Mao Tower China World Trade Center Tower III Chongqing IFS T1 Chongqing World Financial Center CITIC Plaza Diwang International Fortune Center East Pacific Center Eton Place Dalian Fortune Center Gate to the East Greenland Puli Center Guangzhou CTF Finance Centre Guangzhou International Finance Center KK100 Leatop Plaza Longxi International Hotel Minsheng Bank Building Nanjing International Youth Cultural Centre Tower 1 Nina Tower Pearl River Tower Ping An Finance Centre The Pinnacle Shanghai Tower Shanghai World Financial Center Shimao International Plaza Shun Hing Square Suning Plaza 1, Wuxi Tianjin World Financial Center Wanda Plaza Wenzhou World Trade Center The Wharf Times Square White Magnolia Plaza International Commerce Centre International Finance Centre Jiangxi Nanchang Greenland Central Plaza Jin Mao Tower Wuxi Maoye City -- Marriott Hotel Zhongzhou Holdings Financial Center Zhuhai St. Regis Hotel & Office Tower Zhujiang New City Tower Zifeng Tower 23 Marina Abenobashi Terminal Building Skyscraper ( Abeno Harukas ) Abraj Al Bait The Address Downtown Dubai ADNOC Headquarters Al Hamra Tower Almas Tower Arraya Tower Aspire Tower Baiyoke Tower II Burj Al Arab Burj Khalifa Cayan Tower Elite Residence Emirates Office Tower Etihad Towers Haeundae Doosan We 've the Zenith HHHR Tower The Index Jumeirah Emirates Towers Hotel JW Marriott Marquis Dubai Keangnam Hanoi Landmark Tower Kingdom Centre Taipei 101 The Landmark Lotte World Tower MahaNakhon The Marina Torch Northeast Asia Trade Tower Ocean Heights Petronas Towers Princess Tower Rose Tower Telekom Tower World Trade Center Abu Dhabi Europe City of Capitals Eurasia Federation Tower Mercury City Tower OKO Tower The Shard Australia Q1 Under construction North America 3 Hudson Boulevard 3 World Trade Center 9 DeKalb Avenue 30 Hudson Yards 35 Hudson Yards 45 Broad Street 50 Hudson Yards 53W53 111 West 57th Street 125 Greenwich Street Central Park Tower Comcast Technology Center Manhattan West Tower 1 One Vanderbilt Vista Tower Asia China Baoneng Center Baoneng Shenyang Global Financial Center Changsha A9 Financial District Changsha IFS Tower T1 Chengdu Greenland Tower China Resources Centre Block A China Resources Headquarters Chongqing Corporate Avenue 1 Concord International Centre Dalian Greenland Center Dalian International Trade Center Deji Plaza Dongguan International Trade Center 1 Eye of Spring Trade Center Gemdale Gangxia Tower 1 Golden Eagle Tiandi Tower A Golden Eagle Tiandi Tower B Goldin Finance 117 Greenland Group Suzhou Center Guangxi Finance Plaza Haikou Tower Hanking Center Heartland 66 Office Tower Hon Kwok City Center Huaguoyuan Tower 1 Huaguoyuan Tower 2 Jin Wan Plaza 1 Jinan Center Financial City Logan Century Center 1 Mandarin Oriental Chengdu Nanjing Olympic Suning Tower Nanjing World Trade Center Tower 1 Ningbo Center One Shenzhen Bay Phoenix Towers Rose Rock International Finance Center Runhua Global Center 1 Shenglong Global Center Shimao Hunan Center Shum Yip Upperhills Tower 1 South Asian Gate Spring City 66 Suning Plaza Tower 1, Zhenjiang Suzhou IFS Suzhou Zhongnan Center Tianjin Chow Tai Fook Binhai Center Tianjin Modern City Office Tower Tianjin R&F Guangdong Tower Wuhan Center Wuhan Greenland Center Xiamen International Centre Yantai Shimao No. 1 The Harbour Yuexiu Fortune Center Tower 1 India DB Crown Lokhandwala Minerva Namaste Tower Palais Royale Three Sixty West World One Saudi Arabia Capital Market Authority Headquarters Diamond Tower Jeddah Tower Lamar Towers South Korea LCT Landmark Tower LCT Residential Tower A LCT Residential Tower B Parc1 Tower UAE Address Boulevard Ahmed Abdul Rahim Al Attar Tower DAMAC Residenze Dubai Pearl Marina 101 Marina 106 The Skyscraper other Abu Dhabi Plaza The Exchange 106 Gate of Kuwait Gate of Taipei Iconic Tower Merdeka PNB 118 Pertamina Energy Tower Ryugyong Hotel The Stratford Residences VietinBank Business Center Office Tower Vincom Landmark 81 Europe Lakhta Center Australia Australia 108 Construction delayed or suspended Al Quds Endowment Tower Barwa Tower Burj Al Alam Busan Lotte Town Tower Doha Tower and Convention Center Dubai Towers Doha Forum 66 India Tower JW Marriott International Finance Centre Lighthouse Tower Millennium Tower Orchid Heights Pentominium The Pinnacle Plaza Rakyat Qatar National Bank Tower Signature Tower Jakarta Sino - Steel Tower Skycity Square Capital Tower Tameer Commercial Tower Tour Financial Hub Center Two World Trade Center Former World Trade Center ( 1973 -- 2001 ) See also Proposed supertall skyscrapers List of architects of supertall buildings Chicago skyscrapers Tallest buildings 875 North Michigan Avenue Aon Center Franklin Center Trump International Hotel and Tower Two Prudential Plaza Willis Tower Selected buildings with 20 or more floors 35 East Wacker 55 East Erie Street 77 West Wacker Drive 111 South Wacker Drive 155 North Wacker 181 West Madison Street 311 South Wacker Drive 330 North Wabash 333 North Michigan 333 Wacker Drive 340 on the Park 401 East Ontario 500 West Madison 860 -- 880 Lake Shore Drive Apartments 900 North Michigan 1700 East 56th Street ABN AMRO Plaza Allerton Hotel Aqua Bilandic Building The Blackstone Hotel Blue Cross Blue Shield Tower Boeing International Headquarters Carbide & Carbon Building The Chandler Chase Tower Chicago Board of Trade Building Chicago Place Chicago Temple Building City Hall Square Building Civic Opera House Coast at Lakeshore East CNA Center Crain Communications Building Dirksen Federal Building Field Building Fisher Building FOUR40 Four Seasons Hotel Chicago Grant Thornton Tower Harbor Point Hilton Chicago Home Insurance Building Hyatt Center James R. Thompson Center Joffrey Tower Kluczynski Federal Building Lake Point Tower The Lancaster LaSalle - Wacker Building Legacy Tower Leo Burnett Building London Guarantee Building Marina City Masonic Temple Mather Tower Metropolitan Tower Montauk Building NBC Tower Olympia Centre One Magnificent Mile One Museum Park One North LaSalle One North Wacker One Prudential Plaza Optima Signature Outer Drive East Palmer House Hotel Palmolive Building Park Tower The Parkshore Peoples Gas Building Pittsfield Building Plaza 440 Powhatan Apartments Presidential Towers The Regatta Regents Park Richard J. Daley Center River East Center Roanoke Building and Tower The Shoreham Skybridge The Buckingham The Fordham The Heritage at Millennium Park The Grant The Pinnacle Three First National Plaza The Tides Time - Life Building Tribune Tower Virgin Hotels Chicago Waldorf Astoria Chicago Water Tower Place Wrigley Building Chicago Landmark skyscrapers with 12 or more floors 300 West Adams Building The Arc at Old Colony Auditorium Building Brooks Building Bryn Mawr Apartment Hotel Carson, Pirie, Scott and Company Building Chicago Building Gage Group Buildings Heyworth Building Hilliard Towers Apartments Inland Steel Building Manhattan Building Marquette Building Marshall Field and Company Building Monadnock Building Mundelein College Skyscraper Building New York Life Insurance Building Reliance Building Rookery Building See also Architecture Art Deco Chicago City Hall Chicago School Tallest buildings Washington Block United Continental Holdings Current airlines United Airlines Current marketing brands United p.s. United Express Former airlines Capital Airlines Continental Airlines Continental Micronesia New York Air Pan American World Airways People Express Airlines Texas International Airlines Former marketing brands Continental Connection Continental Express Continental Lite Shuttle by United Ted Former holding companies Jet Capital Corporation Texas Air Corporation UAL Corporation Frequent flyer services United Club MileagePlus People William A. Patterson Glenn Tilton Larry Kellner Jeff Smisek Oscar Munoz Walter Varney Robert Six Legal issues Blakey v. Continental Airlines, Inc. Untied.com Customer Service Snafus United Breaks Guitars United Airlines accidents and incidents 1933 Boeing 247 mid-air explosion Trip 4 ( 1935 ) Trip 34 ( 1936 ) 1943 Liberator crash at Whenuapai ( 1943 ) Flight 521 ( 1947 ) Flight 608 ( 1947 ) Flight 624 ( 1948 ) Flight 610 ( 1951 ) Flight 615 ( 1951 ) Flight 409 ( 1955 ) Flight 629 ( 1955 ) 1956 Grand Canyon mid-air collision Flight 736 ( 1958 ) 1960 New York mid-air collision Flight 859 ( 1961 ) Flight 297 ( 1962 ) Flight 823 ( 1964 ) Flight 389 ( 1965 ) Flight 227 ( 1965 ) Flight 266 ( 1969 ) Flight 553 ( 1972 ) Flight 2860 ( 1977 ) Flight 173 ( 1978 ) Flight 2885 ( 1983 ) Flight 811 ( 1989 ) Flight 232 ( 1989 ) Flight 585 ( 1991 ) Flight 826 ( 1997 ) Flight 175 ( 2001 ) Flight 93 ( 2001 ) Flight 3411 incident ( 2017 ) Continental Airlines accidents and incidents Flight 11 ( 1962 ) Flight 12 ( 1965 ) Continental Micronesia Flight 614 ( 1980 ) Flight 1713 ( 1987 ) Flight 55 ( 2000 ) Flight 1883 ( 2006 ) Flight 1404 ( 2008 ) Facilities Willis Tower ( Chicago ) 77 West Wacker Drive ( Chicago ) 1600 Smith Street ( Houston ) 600 Jefferson ( Houston ) American General Center ( former ) List of airline holding companies Timeline of tallest buildings in Chicago First Holy Name Cathedral ( 75 m ) ( 1854 ) Saint Michael 's Church ( 88 m ) ( 1869 ) Chicago Board of Trade Building ( 98 m ) ( 1885 ) Masonic Temple Building ( 92 m ) ( 1895 ) Montgomery Ward Building ( 120 m ) ( 1899 ) Wrigley Building ( 134 m ) ( 1922 ) Chicago Temple Building ( 173 m ) ( 1924 ) Chicago Board of Trade Building ( 184 m ) ( 1930 ) Richard J. Daley Center ( 198 m ) ( 1965 ) John Hancock Center ( 344 m ) ( 1969 ) Aon Center ( 346 m ) ( 1973 ) Willis Tower ( 442 m ) ( 1974 ) Retrieved from `` https://en.wikipedia.org/w/index.php?title=Willis_Tower&oldid=854488231 '' Categories : Airline company headquarters in the United States Buildings and structures on U.S. Route 66 Central Chicago Former world 's tallest buildings Landmarks in Chicago Office buildings completed in 1973 Skyscraper office buildings in Chicago Retail company headquarters in the United States Skidmore, Owings & Merrill buildings United Airlines Tourist attractions along U.S. Route 66 Tourist attractions in Chicago 1973 establishments in Illinois Hidden categories : Webarchive template wayback links Wikipedia indefinitely semi-protected pages Wikipedia indefinitely move - protected pages Use mdy dates from May 2017 Coordinates on Wikidata Articles containing potentially dated statements from December 2013 All articles containing potentially dated statements All articles with unsourced statements Articles with unsourced statements from November 2009 Articles with unsourced statements from February 2011 Structurae ID different from Wikidata Talk View source Contents About Wikipedia Afrikaans Alemannisch Ænglisc Aragonés Asturianu Avañe'ẽ Azərbaycanca বাংলা Беларуская Беларуская ( тарашкевіца ) ‎ Български Bosanski Brezhoneg Català Čeština Cymraeg Dansk Deutsch Dolnoserbski Eesti Ελληνικά Español Esperanto Euskara فارسی Fiji Hindi Français Frysk Galego 𐌲𐌿𐍄𐌹𐍃𐌺 한국어 Հայերեն हिन्दी Hrvatski Ido Bahasa Indonesia Italiano עברית Basa Jawa ქართული Kernowek Kurdî Latviešu Lietuvių Magyar मैथिली മലയാളം मराठी Bahasa Melayu Nāhuatl Nederlands नेपाल भाषा 日本 語 Norsk Norsk nynorsk Occitan Oʻzbekcha / ўзбекча ਪੰਜਾਬੀ پنجابی Polski Português Română Runa Simi Русский Scots Seeltersk Shqip Sicilianu Simple English Slovenčina Slovenščina Soomaaliga Српски / srpski Srpskohrvatski / српскохрватски Suomi Svenska Tagalog தமிழ் తెలుగు ไทย Türkçe Twi Українська اردو Tiếng Việt West - Vlams Winaray Yorùbá 粵語 中文 82 more Edit links This page was last edited on 11 August 2018, at 18 : 37 ( UTC ). 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Question: when did the sears tower change to the willis tower
Answer: July 16, 2009