The US Open Tennis Championships is a hardcourt tennis tournament. Since 1987, the US Open has been chronologically the fourth and final Grand Slam tournament of the year. The other three, in chronological order, are the Australian Open, French Open and Wimbledon. The US Open starts on the last Monday of August and continues for two weeks, with the middle weekend coinciding with the US Labor Day holiday. The tournament is of one of the oldest tennis championships in the world, originally known as the U.S. National Championship, for which men’s singles and men’s doubles were first played in August 1881.