Question: Which shopping and entertainment district in Atlanta, that was first opened in 1969, has the Atlanta Zero Mile Post stone merker in its basement?

Context paragraphs:
Atlanta Zero Mile Post: The Atlanta Zero Mile Post is a stone marker which marked the terminus of the Western and Atlantic Railroad in Atlanta.  It is approximately 1 foot wide on each side and 42 inches tall.  It is inscribed on one side with the text "W & A RR 138" and on another side, "W & A RR OO".  It is located in the basement of a disused building in Downtown Atlanta, within the Underground Atlanta Historic District, under the Central Ave. viaduct, between Alabama and Wall streets.

Zero Mile (Nagpur): Zero Mile Stone (Marathi: शून्य मैलाचा दगड ) is a monument locating the geographical centre of colonial India in the city of Nagpur, Maharashtra.  The Zero Mile Stone was erected by the British who used this point to measure all the distances.  The Zero Mile Stone consists of four horses and a pillar made up of sandstone.  In 2008, The Times of India undertook to maintain the monument for the next 5 years.

Westgate Entertainment District: Westgate Entertainment District, formerly known as "Westgate City Center" is the name of a mixed-use development located in Glendale, Arizona.  Westgate is described as a super-regional destination for shopping, dining, entertainment, and commercial offices.  Funded by millionaire New York architect Ron Elsensohn and anchored by the Gila River Arena, home of the NHL team the Arizona Coyotes, the complex features 8000000 sqft of retail space and is one of the premier entertainment destinations in the region, attracting over 22 million visitors annually.  In 2011, the future of the development came into doubt, as the property went into foreclosure and reverted to lenders.  The shopping center was re-branded and reopened under the name Westgate Entertainment District, operated by Vestar, who also manages other properties in the Phoenix-metro area.

Underground Atlanta: Underground Atlanta was a shopping and entertainment district in the Five Points neighborhood of downtown Atlanta, Georgia, United States, near the Five Points MARTA station.  First opened in 1969, it takes advantage of the viaducts built over the city's many railroad tracks to accommodate later automobile traffic.  Each level has two main halls, still called Upper and Lower Alabama and Pryor Streets.

History of Atlanta: The history of Atlanta dates back to 1836, when Georgia decided to build a railroad to the U.S. Midwest and a location was chosen to be the line's terminus.  The stake marking the founding of "Terminus" was driven into the ground in 1837 (called the Zero Mile Post).  In 1839, homes and a store were built there and the settlement grew.  Between 1845 and 1854, rail lines arrived from four different directions, and the rapidly growing town quickly became the rail hub for the entire Southern United States.  During the American Civil War, Atlanta, as a distribution hub, became the target of a major Union campaign, and in 1864 Union William Sherman's troops set on fire and destroyed the city's assets and buildings, save churches and hospitals.  After the war the population grew rapidly, as did manufacturing, while the city retained its role as a rail hub.  Coca-Cola was launched here in 1886 and grew into an Atlanta-based world empire.  Electric streetcars arrived in 1889, and the city added new "streetcar suburbs".

Kilometre zero: In many countries, Kilometre Zero (also written "km 0") or similar terms in other languages (also known as Zero mile marker, control stations or control points) is a particular location (often in the nation's capital city), from which distances are traditionally measured.  They were markers where drivers could set their odometers to follow directions in early guide books.

Zero Milestone: The Zero Milestone is a zero mile marker monument in Washington, D.C. intended as the initial milestone from which all road distances in the United States should be reckoned when it was built.  At present, only roads in the Washington, D.C. area have distances measured from it.

Atlanta Constitution Building: The Atlanta Constitution Building, also known as the Georgia Power Atlanta Division Building, is located at the northwest corner of Alabama and Forsyth Streets in downtown Atlanta, Georgia, at 143 Alabama Street, SW.  It is located in an area known as the "Heart of Atlanta" straddling the railroad gulch ("The Gulch"), "due to [its] proximity to the 'Zero Mile Post' which marked both the Southeastern terminus of the Western and Atlantic railroad and the city's earliest settlement".  The former Atlanta Constitution Building was designed by Adolph Wittman and was located at the opposite corner of the intersection beginning in 1895.

John Street (Toronto): John Street is a street in Downtown Toronto.  It runs from Stephanie Street and Grange Park in the north to the Metro Toronto Convention Centre on Front Street in the south.  It is home to a number of Toronto's cultural institutions, including buildings for the CBC, CTV, Toronto International Film Festival.  The "National Post" has described it as "Running directly through the entertainment district, its spine connects many great cultural institutions, popular retail outlets, restaurants and soon-to-be-built condos."  The City of Toronto has dubbed the street a "Cultural Corridor" and a report calls it "the centrepiece of the Entertainment District."

Club Quarter: The Entertainment District is located in Springfield, Massachusetts, in the Metro Center district surrounding historic Stearns Square.  Stearns Square is bordered by Worthington Street to the north and Bridge Street to the south; however, the Entertainment District extends for several city blocks north, south, east and west of Stearns Square.  For over 100 years, this area of Springfield, surrounding Stearns Square and Springfield Union Station have been home to the city's most prominent clubs, restaurants, bars, music venues, movies houses, and coffee houses.  Currently, there are over 75 restaurants, nightclubs, and bars in Springfield's Entertainment District, making it the largest entertainment district between New York City and Montreal, Canada.  The Entertainment District is a primary reason why Springfield was recently ranked among America's Top Ten Best Cities for Singles by Yahoo and Sperling's Best Places.

Supporting paragraphs: Atlanta Zero Mile Post Underground Atlanta
Answer: Underground Atlanta