Lake Arrowhead is an unincorporated community and a census-designated place (CDP) in the San Bernardino Mountains of San Bernardino County, California, within the San Bernardino National Forest, surrounding the Lake Arrowhead Reservoir. Lake Arrowhead consists of 6 communities including Lake Arrowhead, Twin Peaks, Blue Jay, Cedar Glen, Sky Forest, and Rim Forest. The population of the CDP was estimated at 12,424 in the 2010 census. It was formerly called "Little Bear Lake", until around 1920, when a group from Los Angeles, the Arrowhead Lake Company, bought the lake and the land surrounding it, and changed its name to Arrowhead Lake.

Lake Arrowhead is an artificial lake located in the San Bernardino Mountains on Little Bear Creek, a tributary of Deep Creek and the Mojave River. It has a surface area of approximately and a capacity of . It is surrounded by the unincorporated community of Lake Arrowhead in San Bernardino County, California.