Idyllwild, Pine Cove, and Fern Valley are three adjacent unincorporated communities in the San Jacinto Mountains in Riverside County, California, United States. Idyllwild has the largest population of the three. For statistical purposes, the United States Census Bureau has defined Idyllwild–Pine Cove as a census-designated place (CDP). The CDP's population was 3,874 at the 2010 census, up from 3,504 as of the 2000 census.