Monument record 0942100000 - Poundon Hill Transmitter Station

Former World War II radio transmitter site. After war, thought to be used as an MI6 Signals Intelligence (SIGINT) site (B1).
Possibly still in use?
From mid June 1942 the Secret Operations Executive (SOE) established a separate wireless network, with four signal stations at Grendon Underwood, Poundon, Bicester and Thame Park. The station at Poundon was codenamed 53B and also communicated with an SOE training school in Canada (STS 103) instructing American agents (B2).

Station 53b Receiver site, a Second World War secret military installation at Poundon Hill is visible on historic aerial photographs and was mapped as part of the North Buckinghamshire Aerial Investigation and Mapping project (EBC18304). Located in a field north of the lane between Poundon Hill and Poundon village and centred at SP 64150 25176, the Special Operations Executive (SOE) Home Station became known as Station 53b, which comprised a rectangular enclosure created by a barbed wire entanglement obstruction about 105 x 52 metres containing three adjoining rectangular buildings. The two main buildings appear separate in 1946 but in 1947 and subsequent years appear to have become joined and slightly extended. These buildings contained the receiver equipment with 40 operating positions, of which over half were adapted for automatic sending. Also installed within the building were Wide Band Receiving Amplifiers giving SOE the ability to operate as many as 50 receivers simultaneously from each amplifier. In the fields to the west, north and east of the receiver buildings is the site’s antennae farm, along with some probable military structures or buildings in fields north of Poundon House and centred at SP 64418 25277. The antennae are not visible on aerial photographs taken in 1946, so may have been dismantled following the war’s end the year before. Between 1961 and 1973, a third rectangular building, about 30 x 8 metres, was added to the west of the original buildings. On aerial photographs taken in 2015, the two original buildings have been demolished and replaced by a larger building, though the later building remain. However, by 2019, aerial photographs show that this building has also been demolished and a larger building stands in its place.

Station 53c Receiver site, a Second World War secret military installation is visible on historic aerial photographs and was mapped as part of the North Buckinghamshire Aerial Investigation and Mapping project (EBC18304). Located on both sides of the road on Poundon Hill and centred at SP 63668 25130, in 1943 the Special Operations Executive (SOE) acted as technical liaison in the design and construction of a wireless receiver station which was then staffed by American personnel from the Office of Strategic Service (OSS) under the guidance of SOE. Much of the internal installation was carried out by the Americans. The site comprises three parts: a smaller site to the west of the lane, the main site to the east of the lane and a sewage works to the southwest of both sites. The camp has numerous rectangular military buildings and huts of various sizes, many of which are connected by corridors, all accessed by a system of footpaths and a road network. The precise function of all the buildings is uncertain, but it seems likely that at least some provided accommodation and other logistical services for the American servicemen operating the receiver site. In the fields to the east of the main station buildings is the site’s antennae farm. The receiving aerial layout consisted of five 3-wire rhombics and the transmitting aerial layout comprised 35 dipole aerial and four 3-wire rhombics. Only a few aerials were mapped still in situ on aerial photographs taken in 1946. It would seem that the site continued to operate during the Cold War by the Diplomatic Wireless Service (DWS) to provide secure communications links with British Embassies worldwide. Aerial photographs taken in 1961 show that the camp buildings remain mostly unchanged after the war and between 1961 and 1966 a large cross-shaped structure has been constructed in the field to the west of the site. Centred at SP 63416 25270, each arm of the cross measures about 44.5 x 5 metres and appears to be a built wall with a small entrance/gap at the end. Within each arm are equally spaced eleven (probably circular) structures about 1 metre in diameter. The function of these structures is unknown and appear to have no height, so possibly represent the bases or plinths for antennae. About 2 metres from the end of each arm is a small triangular structure of uncertain function. At military installations at nearby Gawcott (the post-war transmitter station for Station 53c) and Croughton, similar cross-shaped features were recorded. On aerial photographs taken in 2003, the cross structure has been demolished and is no longer visible in the cultivated field. Similarly, the part of the site located to the west of the road has been entirely demolished and no evidence of its structures or buildings are visible in the field. It is likely that this was decommissioned around 1969 or 1970, but the remaining site is likely to have continued operations into the early 21st century. However, none of the wartime buildings have survived by this time. The remaining site has now been sold off and has become Tower Hill Industrial Park (6-17).