Alconbury Weald is rich in military heritage and will be celebrating its past by opening up some of its secrets on 11 September as part of the National Trust’s Heritage Open Days.

The designs of the current and future development of the former airfield include key listed buildings, which will be preserved and enhanced in heritage settings, as well as a number of echoes of its previous role reflected in the layout of parks and spaces that capture the footprints of history.

On 11 September, Alconbury Weald’s Heritage Open Days event will focus on two important aspects of the old airfield’s historic role: straddling both the RAF and American Air Force eras of the Second World War and the unique Cold War Intelligence role of the Avionics Building (Building 210).

Pre-booked guided tours will give a fascinating insight into the Cold War Avionics building, which was designed to survive a nuclear attack while still analysing reconnaissance taken by the TR1 reconnaissance aircraft (also known as the U2 spy plane). The only permanent base in the UK for these extraordinary aircraft, which flew on the edge of space, Alconbury had hangars exclusively designed for them – two of which will form a Heritage Area alongside Building 210 in a future phase of development.

The Grade II* Listed building was designed and constructed during some of the hottest moments of the Cold War in the 1980s, but it was completed in 1989 as tensions between the West and the Soviet Union thawed. It was one of the largest and most sophisticated building of its kind in the UK at the time, and remains an important monument to the nature of the Cold War and those who served in it.

Bohemia Café & Bistro lies at the heart of the Second World War themed day at Alconbury Weald and the team will be serving a menu reminiscent of the period from its newly opened space in the refurbished World War II listed Watch Office. This building was the first permanent control tower at the airbase, acting as a central operation building for the whole airfield and lies at the heart of the first phase of the development.

The events on Watch Office Green will include live music from The Umbrella Big Band playing classics from the 1940s (at midday) and a performance from Cambs and Beds Lindy Hop dancers (at 3pm). There will also be a display of military vehicles from the Second World War period and a range of events including displays, artefacts, costumes and lawn games on Watch Office Green.

As the day moves into the evening, events move to the nearby, newly opened Pavilion Community Centre where Michael Monk from Stukeleys Heritage Group and his wife Ann will read from the published recollections of Margaret Faulkner and John Lovell, who lived close to the airfield during WWII (at 6pm) and the Airfield Research Group will showcase various artifacts uncovered at RAF Alconbury and share interesting history on some of the listed buildings at Alconbury Weald (at 7pm).

Rebecca Britton from Urban&Civic said: “The military past of Alconbury Weald has shaped the legacy of the land we inherited, and the design of the development moving forward incorporates echoes of the airfield’s history, through key footprints, views and features, as well as the listed buildings. All of these will come together as the development rolls out into a Heritage Trail as well as a specific Cold War Heritage Area that will tell the unique story of this place’s role in intelligence gathering at some of the most frightening periods of our history.

“In the meantime, Heritage Open Days gives us a chance to open up these treasures and provide local residents and communities with an opportunity to discover some of Alconbury Weald’s hidden past and enjoy the activities, performances and presentations taking place throughout the day.”

Heritage Open Days is England's largest festival of history and culture, bringing together over 2,000 local people and organisations, and thousands of volunteers. Every year in September, places across the country throw open their doors to celebrate their heritage, community and history. It’s your chance to see hidden places and try out new experiences.