The Cincinnati Masters is a professional tennis tournament that is part of the ATP Tour and the WTA Tour. It is held annually in August in Cincinnati, Ohio, United States. The Cincinnati Masters is one of the oldest and most prestigious events in the sport, having been first held in 1899. It is also one of the few tournaments on the ATP Tour that is played on a hard court surface. The tournament features a singles draw for both men and women, as well as a doubles draw for both men and women. The Cincinnati Masters is considered to be one of the most important tournaments leading up to the US Open, which is held later in the same month, and has a reputation for attracting top players from around the world. Past winners of the Cincinnati Masters include tennis legends such as Pete Sampras, Roger Federer, and Serena Williams.