The Henley Royal Regatta is a prestigious rowing event held annually on the River Thames in Henley-on-Thames, England. Established in 1839, it attracts top rowing clubs and athletes from around the world. The regatta features a series of races over a 1,640-meter course, with crews competing in various categories, including eights, fours, and singles. The event typically takes place in early July and lasts for five days. It is known for its unique format, where boats race head-to-head in knockout rounds. The regatta also has a rich tradition, with spectators often dressing in formal attire to enjoy the races and the festive atmosphere.