Camp Callan was a United States Army anti-aircraft artillery replacement training center that was operational during World War II.

It was located on the southern West Coast of the United States, in the La Jolla community of San Diego, California.

Camp Callan was located near U.S. Highway 101, about 15 miles (24 km) north of downtown San Diego in the La Jolla area.

This portion of the former base is in the vicinity of present-day Genesee Avenue and North Torrey Pines Road.

On October 9, 1940, the San Diego City Council leased the U. S. military 710 acres (2.87 km2) of land for a nominal one dollar per year.

On November 22, 1940, the War Department announced plans to create a replacement training center for coast artillery units in the Torrey Pines Mesa area.

Men inducted into the military under the Selective Service Program would be assigned to this new training center.

The purpose of this training center was to teach trainees how to fire long-range weapons in the event the Imperial Japanese Navy tried to attack the West Coast of the United States.

Construction of the base began in November 1940 and official occupation of the camp was marked by a military flag-raising ceremony that took place on January 15, 1941.

In addition to artillery gun positions and small arms ranges, a variety of other facilities and structures were built on the base.

Various living amenities were provided for the health, general education and war training schooling of the trainees, much like other Army camps of the time.

In the last group of recruits attending Coast Artillery basic training at Camp Callan, was Donald Prell, who in June 1944, graduated from OCS at Ft. Benning, GA.

The anti-aircraft training program was transferred to Fort Bliss in Texas, and the camp assumed an important role in preparations for massive overseas amphibious assaults.

At the time the camp closed, Southern California was facing a shortage of lumber and building materials.