Question:  Alligator wrestler Tahar Douis performed at which Las Vegas hotel, that was later demolished to make way for the Global Business District? 
Context: The Castaways Hotel and Casino, formerly the Showboat Hotel and Casino was a hotel and casino located at the north end of the Boulder Strip in Las Vegas, Nevada.  The hotel consisted of a 19 story tower containing 445 rooms, a casino and an adjacent RV park.  The Castaways hotel was demolished on January 11, 2006 to make way for an unknown project. Tahar Douis is a Moroccan wrestler of alligators known for hypnotizing them and putting his head inside their open jaws.  He was born in the 1950s in Marrakech, left home at age 6 to join a group of street performers, and later began performing for the London-based Circus Hasani at age 16.  In the 1980s he was taught by Bob Tiger, a great third-generation Seminole gator wrestler from the Florida Everglades.  Previous to his career as an alligator wrestler, he was a snake charmer and circus strong man.  As a strong man, he earned a Guinness World Record in the 1970s by carrying 12 men weighing a total of 1,700 pounds on his shoulders, forming the world's heaviest human pyramid.  In the late 1980s his alligator show was a star attraction in the Ringling Bros. and Barnum & Bailey Circus as part of their "Safari Fantasy" themed shows.  By the middle of the 1990s he was wrestling gators as part of the "Splash" show at the Riviera in Winchester, Nevada on the Las Vegas Strip. The Grand Central Palace was an exhibition hall in New York City.  Built in 1911, the 13-story building was located on Lexington Avenue between 46th and 47th Streets, occupying the air rights over the railroad tracks leading into Grand Central Terminal.  The Palace was designed by Warren and Wetmore and Reed and Stem, who had collaborated on Grand Central Terminal.  It replaced the original Grand Central Palace, built in 1893 on Lexington Avenue between 43rd and 44th Streets and demolished by 1913 to make way for the Grand Central development after it had served as a temporary station during the building of the terminal.  The Palace was New York's main exposition hall until it closed in 1953.  Its location and the proximity of Grand Central Terminal spurred the construction of a hotel district in the area.  The new Grand Central Palace was demolished in 1964 to make way for 245 Park Avenue. Riviera (colloquially, "the Riv") was a hotel and casino on the Las Vegas Strip in Winchester, Nevada, which operated from April 1955 to May 2015.  It was last owned by the Las Vegas Convention and Visitors Authority, which decided to demolish it to make way for the Las Vegas Global Business District. Downtown Las Vegas (commonly abbreviated as DTLV) is the central business district and historic center of Las Vegas, Nevada.  It is the original townsite and was the gambling district of Las Vegas prior to the Strip, and the area still incorporates downtown gaming.  As the urban core of the Las Vegas Valley, it features a variety of hotel and business highrises, cultural centers, historical buildings and government institutions, as well as residential and retail developments.  Downtown is located in the center of the Las Vegas Valley and just north of the Las Vegas Strip, centered on Fremont Street, the Fremont Street Experience and Fremont East.  The city defines the area as bounded by I-15 on the west, Washington Avenue on the north, Maryland Parkway on the east and Sahara Avenue on the south. The Westgate Las Vegas Resort & Casino is a hotel and casino in Winchester, Nevada.  It is owned by Westgate Resorts and operated by Navegante Group.  It has 2,956 hotel rooms including 305 suites.  It opened in 1969 as the International Hotel, and was known for many years as the Las Vegas Hilton, then briefly as the LVH – Las Vegas Hotel and Casino.  It was renamed the Westgate Las Vegas on July 1, 2014. The Westin Las Vegas Hotel & Spa is a resort near the Las Vegas Strip in Paradise, Nevada.  The Westin is managed by Pyramid Hotel Group, under franchise from Starwood Hotels & Resorts Worldwide, owner of Westin Hotels.  It is noteworthy for being one of the first Las Vegas resorts to prohibit smoking in almost all parts of the property. The Las Vegas metropolitan area is home to many sports, most of which take place in the unincorporated communities around Las Vegas rather than in the city itself.  The Las Vegas Valley has one major league professional team: the Vegas Golden Knights of the National Hockey League (NHL) who began play in 2017 as the region's first major pro team.  The Oakland Raiders of the National Football League (NFL) will begin play in Las Vegas as the "Las Vegas Raiders" by 2020 and become the region's second major professional team.  Las Vegas is also home to one minor league sports team: the Las Vegas 51s of the Triple-A Pacific Coast League (Minor League Baseball).  The 51s are currently the only team to actually play in the city of Las Vegas, playing at the city owned Cashman Field.  They will be joined in 2018 by the Las Vegas Lights FC of the United Soccer League, one of two leagues that collectively make up the second level of the U.S. men's soccer league system. The Guardian Angel Cathedral is a cathedral of the Catholic Church in Winchester, Nevada.  It is located at 302 Cathedral Way, just off the Las Vegas Strip, near the Encore Las Vegas hotel.  Since the creation of the Diocese of Las Vegas in 1995, Guardian Angel has been the seat of the bishop, previously having been a parish of the Diocese of Reno. Sky Las Vegas is a 45-story luxury high-rise condominium tower with 409 units, situated on a 3-acre site on the Las Vegas Strip in Winchester, Nevada.  The tower's land, as well as nearby property, had been the site of the El Rancho Vegas hotel and casino from 1941 to 1960, when it burned down.  The property remained vacant for decades.  A two-story retail project had been planned for a portion of the site in 2001, although it ultimately did not materialize.  Plans for Sky Las Vegas were announced in July 2004, with construction beginning the following year and its opening occurring in May 2007.
Answer: Riviera