The 1900 U.S. National Championships was a tennis tournament that took place in June and August of 1900. The women's tournament was held from June 19 to June 23 on the outdoor grass courts at the Philadelphia Cricket Club in Philadelphia, Pennsylvania. The men's tournament was held from August 13 to August 21 on the outdoor grass courts at the Newport Casino in Newport, Rhode Island. It was the 20th U.S. National Championships and the second Grand Slam tournament of the year. US Open 1900: August 13–13, 1900. Men's singles: Malcolm Whitman — 3rd major title. Women's singles: Myrtle McAteer. Wiki link