Castaic, California, is a census-designated place in Los Angeles County, California, north of Santa Clarita and a few miles from Six Flags Magic Mountain amusement park. It is approximately 39 miles (63 km) from the downtown Los Angeles Civic Center. As of the 2010 Census, Castaic had a population of 19,015. The community has a ZIP Code of 91384 and area code of 661.
The origin of the name Castaic is the Chumash Native American word Kashtuk, meaning "eyes." Modern Castaic began in 1915 with the opening of the original Ridge Route, which brought travelers looking for gasoline, water, food and lodging to the community. Some of the earliest businesses started in Castaic are Castaic Brick (founded 1927) and George Dunn's Wayside Dairy (founded 1929). Sam's Place (Sam Parson, proprietor) on the Ridge Route has long since gone and is now a memory. Castaic is a major truck stop along the Interstate 5 freeway.
Castaic covers 7.3 square miles (18.9 km2) of area and includes the Val Verde and Chiquito Canyon areas. Castaic Lake is the southern terminus of the west branch of the California Water Project, and a 1,175-megawatt pumped-storage hydroelectric plant at the north end of Lake Castaic captures the energy from the falling water descending toward the Los Angeles area.