A house on the bluffs at Camp DeWolfe in Wading River, covertly used as an FBI radio transmission station during World War II to gather military intelligence, has been added to the state and national registers of historic places.

FBI radio operators impersonating German agents used the Wading River Radio Station to communicate with the German intelligence service, according to the site’s registration form with the National Register of Historic Places.

Information covertly gathered by agents at the radio station was critical to inspiring the United States’ development of an atomic bomb.

The station was also involved in the Operation “Bodyguard,” which used counterintelligence to confuse and mislead the Nazi government about the upcoming Allied invasion of Europe.

The radio station operated from 1942 to 1945.

It was established after a Spanish businessman who had been coerced by Abwehr, the German military intelligence service, to work as a spy, approached an FBI agent because he wanted to serve as a double agent, according to the national register.

The FBI, after vetting the Spaniard, helped him set up the secret radio station the Germans had charged him with establishing to broadcast and receive information directly from a site in Hamburg, Germany.

The FBI found and rented the house in Wading River, which was then on a 71-acre heavily wooded site owned by the Owen family, which bought the property and built the house circa 1912 near the edge of a high cliff roughly 100 feet above the beach.

In January 1942, FBI engineers installed radio equipment in the house, hid a large antenna in the woods, and built a diesel-powered generator using an automobile engine to avoid local suspicion about electricity consumption at the house, which was far greater than what was then the norm due to the radio operations. An FBI agent assigned to manage the operation moved in with his family — and two or three radio operators. The first floor was maintained as the agent’s family home, while the second and third floors were used for the FBI operation, according to the national register registration narrative. They remained there for the duration of the war.

The operation was closed and the equipment dismantled in June 1945. Soon afterward the Episcopal Diocese of Long Island purchased the property and developed Camp DeWolfe, a retreat center and summer camp. About 25 camp buildings were built on the formerly heavily wooded property around the house, but the house itself and the land around it remain intact, according to the national register document.

The home was built by an Orange County carriage maker, Gabriel S. Owen (1833-1915) as a retirement home, where he lived with his granddaughter until his death. The home stayed in the family, though by the 1930s Owen family members were no longer living there. Then the FBI came calling.

The FBI had been looking for a spot to locate the transmission station for the spying operation and were attracted by the home’s cliffside location and the site’s remoteness. According to the national register registration document:

“By January 1942 [an FBI radio engineer] had stumbled upon the Owen House located in the tiny fishing and farming hamlet of Wading River, New York. Located eighty miles east of New York on Long Island’s North Fork the spacious three story building sat on a cliff bordered on one side by Long Island Sound and acres of dense trees on the other three sides, and the only approach to the station was a bumpy, rutted quarter mile path. Even by today’s standards the house is not easy to find. In 1942 it would have been nearly impossible.”

An FBI agent’s inquiry took the Owen family by surprise. They were sworn to secrecy.

The FBI installed an agent with his wife and infant child in the home. The cover story: the man was a wealthy NYC lawyer rumored to have tuberculosis and in need of the fresh air that the site provided. His cover led local residents to worry about the spread of his disease and discouraged visitors.

The radio station began operating on Jan. 28, 1942. German military intelligence sent instructions to its spy — the Spanish businessman working as a double agent — requiring information about the demand for raw materials and fabricated products, delivery schedules for fighter aircraft and artillery shells and “one final ominous order to ‘deduce artificially the uranium or other ally which may be substituted thereof as an atom constructor,’” according to the book, “Hoover’s Secret War against Axis Spies” (2014) by Raymond Batvinis, which is quoted in the national register registration document. These and similar instructions relayed to the double agent helped the U.S. make the decision to go ahead with production of the atomic bomb.

Because of the extreme secrecy of the operation, “almost seven decades passed before the nature and importance of their work to the Allied victory was even discovered,” according to the national register document.

“Sadly, witnesses to the Wading River Radio Station’s role are now all gone. But perhaps in the future as additional classified records become available for research even more will be learned about the historical importance of this remarkable site.”

The 71-acre Owen property was purchased by the Episcopal Diocese of Long Island in 1947, then led by Bishop James P. DeWolfe. The purchase was accomplished with a bequest by Mary Benson, of Brooklyn. The Wading River Radio Station was subsequently renamed Benson House by the camp and serves as the lodging quarters for camp administration, clergy and some staff.

On the 70th anniversary of D-Day in 2014, the Society of Former Special Agents of the FBI had a gathering and installed a plaque on Benson House to recognize the significance of the Wading River Radio Station.

The plaque reads:

From January 1942 to June 1945 FBI agents and radio technicians secretly living and working at Benson House, broadcasted radio messages to the Germans in Hamburg who believed they were communicating with their espionage agents in the United States. Working closely with military deception planners, the FBI sent hundreds of accurate and fictitious reports designed to confuse and mislead the Nazi leadership regarding Allied military plans and intentions.

Among Benson House’s most significant World War II contributions was the receipt of a German message in April 1942 instructing its spies to obtain information about American atomic bomb development; an order that helped influence President Franklin D Roosevelt’s decision to pursue an atomic weapon. Messages transmitted from Benson House helped deceive the German high command about the timing and location of the June 6th, 1944 Allied invasion at Normandy while others misled Japanese forces about US advances in the Pacific Theater of operations.

This plaque is erected by the Society of Former Special Agents of the Federal Bureau of Investigation to remember Benson House and to pay tribute to the FBI personnel who worked here for their wartime sacrifices and contributions. June 6, 2014.

The registration form for the National Register of Historic Places was prepared by Raymond Batvinis and Matt Tees for Camp DeWolfe in February.

Gov. Andrew Cuomo on Friday announced the listing of this site on the New York State register and the National Register of Historic Places, along with 19 other historic sites throughout the state.