Hemet is a city in the San Jacinto Valley in Riverside County, California, United States. It covers a total area of 27.847 square miles (72 km2), about half of the valley, which it shares with the neighboring city of San Jacinto. The population was 78,657 at the 2010 census.
Hemet was founded in 1887, predating the formation of Riverside County, and was incorporated on January 20, 1910. The formation of Lake Hemet helped the city grow and prosper, and stimulated agriculture in the area. The city is known for being the home of "The Ramona Pageant", California's official outdoor play. Started in 1923, the play is one of the longest running outdoor plays in the United States. Hemet has been named a Tree City USA for 20 years by the Arbor Day Foundation for its dedication to the local forest. The city is home to the Hemet Valley Medical Center, a 320-bed general hospital.
The Cahuilla tribe were the initial inhabitants of the Hemet area. During the early 19th century, the land was used for cattle ranching by Mission San Luis Rey, which named the area Rancho San Jacinto. In 1842 José Antonio Estudillo received the Rancho San Jacinto Viejo Mexican land grant. In 1887, during the first major Southern California land boom, W.F. Whittier and E.L. Mayberry founded the Lake Hemet Water Company, the Hemet Land Company, and the city of Hemet. In 1895, the Hemet Dam was completed on the San Jacinto River, creating Lake Hemet and providing a reliable water supply to the San Jacinto Valley. This water system was a major contribution to the valley's development as an agricultural area. The area's original inhabitants, the Soboba Cahuilla were moved to the Indian reservation near San Jacinto.