The National Challenge Cup was established in 1914 by the newly-organized U. S. Football Association (USFA) as a national championship trophy. The competition was originally open to amateur and professional teams.
There were so many entries for the competition in 1923 that the USFA decided to start another tournament and offer another trophy, the National Amateur Challenge Cup, for amateur teams.
The first amateur tournament wasn't completed, though, because of bad weather, so the new trophy wasn't awarded until 1924.
From 1928 through 1968, the National Challenge Cup championship was usually a two-game, home-and-away series. If each team won a game, they played a third game to determine the champion. Twice, however, the teams were named co-champions history
The National Challenge Cup is now known as the Lamar Hunt U. S. Open Cup, in honor of the long-time soccer promoter who helped found both the North American Soccer League and Major League Soccer. After preliminary rounds, 32 teams are selected for the single-elimination tournament and they're divided into eastern and western brackets, with eight seeded teams in each bracket. If a game ends in a tie, there are two 15-minute sudden-death overtime periods. If neither team scores in overtime, the winner is decided by penalty kicks.
The U. S. Women's Open Cup tournament was established in 1996.