VINTAGE Snapback Hat Lucky Duck Contender Riviera Hotel & Casino Las Vegas Neverworn! The Riviera was the first skyscraper in the Las Vegas Valley, and was the area's tallest building until 1956. Various hotel additions would be made in later years, including a 12-story tower in 1966, a 17-story tower in 1975, and a 24-story tower in 1988. By the time of its closure in 2015, the resort included a 103,800 sq ft (9,640 m2) casino and 2,075 rooms.