World War II Radar Station: B-71

B&W two buildings on left side of hill with evergreen tree
WWII era Radar Station B-71 and its power station were disguised as a farm.

National Park Service

Quick Facts
Coastal Drive. West of Klamath, CA
Disguised WWII Radar Stations
National Register of Historic Places

Historical/Interpretive Information/Exhibits, Parking - Auto

The Klamath River Radar Station B-71 is a rare, surviving World War II early-warning radar station. This kind of radar station was the first step towards a more sophisticated and pioneering early-warning radar defense network.

Access to the trailhead is on the Coastal Drive which is a narrow, gravel road. It is not recommended for recreational vehicles, busses, or any vehicle towing a trailer.


Why build?
As a result of the attack on Pearl Harbor and in the Aleutian Islands, the necessity of guarding American coastlines became more urgent on the Pacific Coast than on the Atlantic. The threat was further demonstrated when a Japanese submarines shelled an oil refinery north of Santa Barbara, California, on February 23, 1942; Esteven Point in British Columbia, Canada, on June 20, 1942, and again at Fort Stevens, Washington, on July 21, 1942. On September 9, 1942, a Japanese submarine-launched aircraft dropped incendiary bombs on Oregon forests roughly 40 miles north of the Klamath River.

The radar station, in what is now Redwood National Park, was built in late 1942 and early 1943 as the northernmost California station in a network of 72 proposed stations, 65 of which were actually built, stretching from the Canadian border into Mexico.

About the Station
The Klamath station was designated by memorandum dated November 6, 1942 as Station B-71, named "Trinidad." It was also referred to as the "Klamath River" station.  The complex included a Power Building, Operations Building, a privy and anti aircraft guns. The radar station was built immediately adjacent to, if not partly on, the historic old Trinidad-Crescent City wagon road.

Rather than using camouflage materials, the buildings of Radar Station B-71 were constructed to resemble farm buildings to disguise their true purpose. The station consisted of three buildings: a power building disguised as a farmhouse, an operations building disguised as a barn and a functional wood frame two-stall privy or outhouse.

The station was manned by members of the Army Air Corps quartered in barracks near the town of Klamath. It was commanded during part of 1943 by a 2nd Lieutenant Neff, later replaced by one or more 1st lieutenants in succession. One day's operation of the station required a crew of about 35 men to cover the 24 hours in shifts. It was guarded by military police with dogs.

Operations Building
The operations buildings was disguised to look like a barn. A false barn door at the north end sat under a roof gable, simulating the track for a traveling pulley hoist which in a genuine barn would be used for moving bales of hay. The exterior walls of the "barn" were disguised with a false wood wall whose outer edge was five or six inches beyond the outer face of the concrete block wall.

The interior of the operations building was divided into about seven rooms. The rooms had acoustic tile ceilings; some had acoustic wall tiles. During the first half of 1943 a mobile SCR-270B radar antenna, consisting of a rectangular metal grid mounted vertically on a pole of triangular metal framework, the whole assembly carried on a wheeled trailer to make it mobile, was installed uncamouflaged about 30 feet west of the operations building. Later more permanent antenna installed.

Power Building
As its name implies, the power building housed the power generators necessary to power the radar equipment.  The power building was located south of the operations building. It was camouflaged or disguised by design to look like a farmhouse. Its wood-shingled gable roof sits on top of the shingled roof—they do not penetrate through the shingles to the attic of the structure. The dormers are for the purpose of making this building appear to be a residential structure, when in fact it was an industrial structure housing an electrical generator to power the radar. The gable ends and exterior false walls were of vertical board and batten siding on a wood frame secured to the concrete block walls. Into these false walls, a number of fake windows were built which did not penetrate the concrete block walls.

The two-stall privy was located 95 feet north of the operations building and has largely eroded away.

About southwest of the power building is the remains of a circular pit about twelve feet in diameter which may have been the location of one of the three 50 caliber machine guns on anti-aircraft mounts which protected the station. Northwest of the operations building is the remains of a similar circular pit which is believed to be the site of a second 50 caliber machine gun. The third site of a gun mount in unknown.

End of Service
As the threat of Japanese attack waned towards the end of World War II, the coastal early radar stations began to be phased out. But with the need for early-warning radar decreasing, the need for air-sea rescue radar increased, and effective July 1, 1944, the Klamath station was converted to emergency rescue service, with the SCR-271 radar replaced with the RC-150 IFF equipment. Station B-71 was thus one of only 22 radar stations on the Pacific Coast, which remained operational until the end of World War II.

Preserving the Station
After the war, Station B-71 was abandoned and reverted to private ownership after the war, until the National Park Service acquired it with the creation of Redwood National Park. The topography of the site has created a conservation challenge with runoff and erosion causing mud to be deposited against the structure. The constant moisture has also damaged the remaining siding in some areas.  Unfortunately, no photographic evidence of the site is known to exist from its wartime use.  First known photographs of the site date to the 1970s.

Despite standing empty since the end of World War II, the radar station remains of the few remaining radar stations in US.  It is on the National Register of Historic Places.


Redwood National and State Parks

Last updated: April 21, 2022