The National Gas Turbine Establishment (NGTE Pyestock) in Fleet, England was the UK’s focal site for developing and testing gas turbines and jet engines. Pyestock was a former golf course between Farnborough and Fleet and was chosen for its location in a secluded woodland spot where noise would be dampened and the NGTE’s activities could be kept away from public view as the project was top secret.
The facility was built in 1942 when the Royal Aircraft Establishment (RAE) Turbine Division moved to Pyestock about 36 miles (58 kilometres) to the West of London. At this stage, the United Kingdom was still in the midst of World War II and jet engine technology was highly sought after. In 1944, the RAE Turbine Division was merged with Power Jets Ltd and in 1946, the new entity became known as the National Gas Turbine Establishment. A new facility was planned on a disused golf course to be known as NGTE Pyestock. This new test site opened in 1949.

A test facility at NGTE Pyestock.
With the advent of supersonic travel, the facility expanded and NGTE Pyestock became the largest facility of its type in the world. Engines for the V Bomber, Harrier and Tornado were tested at the facility. The air house allowed the engine for Concorde to reach over 2,000 mph (3,200 kph).

Inside one of the engine test buildings in the earlier days.
In 1995, the National Gas Turbine Establishment was merged into DERA, the Defence Evaluation and Research Agency, which had its headquarters in nearby Farnborough. NGTE Pyestock was closed and decommissioned in 2000. DERA was split the following year into the Defence, Science and Technology Laboratory (Dstl) and a commercial firm, QinetiQ.

Apart from all of the pipes, you can see an engine test facility in this picture.
An entire website exists at www.NGTE.co.uk. The following is from its introduction page.
For over fifty years, Pyestock was host to the development and testing of gas turbine engines. From the 1950s through to the 1970s, it was the largest facility of its type in Europe (if not the world), and the design, experimentation and testing at Pyestock helped to usher in the jet age. From running up Concorde’s Olympus jet engines in a simulated supersonic conditions through to the endurance checking of every gas turbine installed in the ships of the Royal Navy, Pyestock’s credentials were extremely impressive.
As gas turbine research matured and computer simulations took over, Pyestock was gradually run down and now stands unused. The structures on the site are considered to be of national, if not international, importance. But due to their extremely specialised nature, no alternative uses have been put forward, and the whole site is destined to be demolished and replaced by a supermarket distribution centre.
However, in this transitional period at it waits its fate, Pyestock has become an unofficial museum. The entrance fee is a combination of dexterity, intelligence and courage. Those able to pay are constantly amazed and inspired by what they find; and are saddened that one of the most important research sites in the world is to be swept away and forgotten.
Abandoned: 2000
I worked at NGTE from 1970 to 1975 and it was one of the best career groundings I could ever have got. I have happy many memories of my time there and my involvement in the MRCA (Tornado) , Harrier and Concorde projects. Sad to see it the way it is, but time waits for no one I guess.