The United States Open squash championships is an annual squash tournament sponsored by U.S. Squash. The championship was inaugurated in 1954 as an opportunity for professionals and amateurs to compete against each other. Prior to the mid-1980s, the tournament was held using the hardball squash format (a North American version of squash, which uses a smaller court and a faster-moving ball than the international "softball" version). In 1966, the championship merged with the Canadian Open and became the North American Open. The North American Open continued to use the hardball format and came to establish itself as the most prestigious event in the hardball game. In 1985, the United States Open was reinstituted as a "softball" squash event using the international format. A separate North American Open competition has continued to run as a hardball event. read more