The 2,995-room Cosmopolitan of Las Vegas will begin constructing a new venue in March, a 50,000-square-foot theater that will accommodate about 3,000 guests. The Chelsea, as it will be called, is scheduled to open at the end of 2013. To be used for concerts and sporting events, the venue will be accessible from the West End Tower on the third level and will be available to groups. A staircase will lead from the Grand Lobby up to a VIP level, which will include about 10 private opera boxes and a hospitality room. The resort's former Chelsea Ballroom will be renamed soon.