History of Riverside, California  Riverside, California, was founded in 1870, and named for its location beside the Santa Ana River. It became the county seat when Riverside County, California, was established in 1893. Prior to the colonization of Mexico and Alta California by Spain, the land that would become Riverside, California, was frequented by various Native American people. No permanent settlements are known to have existed, but occasional villages close to the river were documented by later explorers. Artifacts found at White Sulphur Springs, as well as grain grinding holes in rocks south of Mount Rubidoux, provide evidence of the Native American activity. On March 20, 1774, Juan Bautista De Anza, leading an exploratory expedition to find a good land route from southern Mexico to Alta California, reached the area today known as Riverside. He, and others in his contingent, described the area as a beautiful place fragrant with rosemary and other herbs, and having rich grasslands for their horses and cattle to graze. He named the area "Valle de Paraiso", or Valley of Paradise. This was the first official record made of what was to become the city of Riverside. De Anza lead a second expedition through the area on December 31, 1775. This expedition was a colonizing expedition headed for Monterey. They spent New Year's Eve on the banks of the Santa Ana River, and crossed the river the following day. The routes taken by the two expeditions are believed to have followed a course from somewhere near Lake Perris, in current-day Moreno Valley, down the Box Springs grade near the 60/215 Highway interchange, and across Riverside in the direction of the Martha McLean – Anza Narrows park. A marker in the park was dedicated to recognize the point where the group crossed the Santa Ana River. To commemorate De Anza's expeditions, the city of Riverside, through private donations and a federal grant from the Works Progress Administration, began work on a 20-foot statue of De Anza in 1939. The dedication took place in May, 1942, at the corner of Market and 14th streets. The California Silk Center Association was established in November, 1869, and included some of the land that would later become Riverside. The Association dissolved in April, 1870, when Louis Prevost, the only member of the Association knowledgeable on silk farming, passed away unexpectedly. On September 12, 1870, the Southern California Colony Association of Jurupa was formed, and on September 14th they purchased much of the Silk Association's land and water rights.