What tournament is annually held in Las Vegas since the 1970s?
World Series of Poker The World Series of Poker (WSOP) is a series of poker tournaments held annually in Las Vegas and, since 2005, sponsored by Caesars Entertainment Corporation (known as Harrah's Entertainment until 2010). It dates its origins to 1970, when Benny Binion invited seven of the best-known poker players to the Horseshoe Casino for a single tournament, with a set start and stop time, and a winner determined by a secret ballot of the seven players.
Memphis Open (tennis) The Memphis Open, is a professional tennis tournament founded in 1975 that has been held at the Racquet Club of Memphis in Memphis, Tennessee since 1977. The Memphis Open is the only ATP event in the United States that is played on indoor hard courts and usually takes place in February. For part of its history it was a combined men's and women's tournament but as of 2014 it is solely a men's tournament.