Lake Forest is a city in Orange County, California. The population was 77,264 at the 2010 census.
Lake Forest incorporated as a city on December 20, 1991. Prior to a vote of the residents in that year, the community had formerly been known as El Toro since the 1880s. Since being incorporated, Lake Forest has expanded its limits to include the communities of Foothill Ranch and Portola Hills. Foothill Ranch and Portola Hills are master planned developments that brought new homes and commercial centers to the Eastern boundary of Lake Forest throughout the 1990s. Lake Forest (along with its neighboring cities Mission Viejo and Irvine) is ranked as one of the safest cities in the country. The private research firm Morgan Quitno ranked Lake Forest as the 15th safest city and another firm later ranked Lake Forest 10th in 2007 in the United States.