Silver Strand Training Complex

Silver Strand Training Complex South (SSTC-S), formerly known as the Naval Radio Receiving Facility (NRRF), is the premier training facility for U.S. Special Operations Forces. Located between Imperial Beach and Silver Strand State Beach near San Diego in southern California, USA, this facility was known by locals as the "elephant cage" which is a nickname for the large Wullenweber direction finder antenna. The antenna was used to provide direction finding, primary communication links for U.S. Navy submarines. The antenna was finally dismantled in 2015, even though it was scheduled to be removed in fiscal year 2007. Presently the area is part Naval Base Coronado and commanded by that base's Commanding Officer.

Initially created in 1920 as the Navy Radio Compass Station, it was renamed in 1940 as the Navy Direction Finder Station when a permanent direction finding station was established. In 1943, thirty WAVES were stationed there, culminating in 1945 with a total of 112 WAVES; there they engaged in SIGINT. By 1953, it was known as Naval Radio Receiving Station Imperial Beach, and in 1965 it received its well known Wullenweber Circular Disposed Antenna Array, a AN/FRD-10. The last of its type to be built, it ceased operation in 1999.

In 1942, the United States Army took ownership of 412.14 acres in Coronado Heights and designated it Fort Emory in honor of BG Emory, itself being subordinate to Fort Rosecrans, being manned by the 19th Coastal Artillery.Armament of the base consisted of four 155mm guns of Battery Imperial, which was superseded by the two 6 inch guns (M1905) of Battery Grant. Coastal radars were authorized in 1943. Construction of a 16 inch battery were completed in 1944, however the guns were never mounted; these guns would have supplemented the 16 inch Battery Ashburn at Fort Rosecrans. The land upon which the fort was located was turned over to the Navy in 1947, with a single army family as caretaker of the facilities which was declared surplus a year later; in 1950 it was finally transferred to the Navy integrating with the Imperial Beach Radio Station.

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