Rancho San Diego, California landscape and open-space maintenance. Rancho San Diego is served by the Cajon Valley Union School District and the Grossmont Union High School District. Steele Canyon High School and Valhalla High School are the primary schools in this location. Rancho San Diego is also home to the Cuyamaca College Coyotes. Rancho San Diego, California Rancho San Diego is a census-designated place (CDP) in San Diego County, California. The population was 21,208 at the 2010 census, up from 20,155 at the 2000 census. The area was developed as subdivisions beginning in the 1970s. Rancho San Diego is located at (32.765985, -116.921477). According
National Register of Historic Places listings in San Diego County, California were once listed but have been removed. National Register of Historic Places listings in San Diego County, California This is a list of the National Register of Historic Places listings in San Diego County, California. This is intended to be a complete list of the properties and districts on the National Register of Historic Places in San Diego County, California, United States. Latitude and longitude coordinates are provided for many National Register properties and districts; these locations may be seen together in an online map. There are 149 properties and districts listed on the National Register in the county, including