Hope Cove was a World War II radar station. In the early 1950s it was revamped as part of the RAF's Rotor air defence scheme. It was one of five stations equipped with a type R6 (semi-sunk) bunker. The others were Hack Green, Langtoft, St. Twynells and Treleaver.
In the late 1950s the site was taken over by the Home Office and the R6 bunker was turned into a Regional Seat of Government (RSG). Later it became in turn a Sub-Regional Control (SRC), Sub-Regional Headquarters (SRHQ) and Regional Government Headquarters (RGHQ) under various Home Office schemes.
Reports that the bunker was totally refurbished in the 1970s and that it is almost identical to Hack Green are untrue. Apart from relatively minor improvements to electrical wiring and communications, most of the facilities date back to the Rotor era. The building still has its original air-conditioning plant, and most of the teak false floors are still in place.
This site is also known as Bolt Head and, as an RSG, was codenamed Gull Perch.
Today, the interior of the bunker remains in excellent condition, and the filtration plant, generator and other items remain. It was sold to a private buyer in around 2003, and it is unknown what the intentions are for its future use. ( update - I called the new buyer last year (2014) and I think its going to be a hotel complex ! )