What makes RAF Fairford one of the UK's most important military sites?

All eyes have been on RAF Fairford this week after a major incident was declared at the military airbase and a counter-terror investigation launched.

It started in the early hours of Sunday when three vans were spotted near the site prompting a huge police operation. Five men who were arrested on suspicion of offences under the Explosives Act were released on bail on Monday.

The base, located on the border of Gloucestershire and Wiltshire, was opened in January 1944 and has been an important base for US military operations since the Cold War.

Recently the site has been used to support operations targeting Iran's missile capabilities.

But why has the site become one of the UK's most important military bases?

RAF Fairford has been used for various reasons since it opened 82 years ago.

It was originally built in 1944 in preparation for D-Day, when troop carriers and gliders from Fairford were used for the Normandy landings on 6 June the same year.

The site was also used to lift British troops for Operation Market Garden in the German-occupied Netherlands in September 1944.

In the Cold War, the US air force (USAF) occupied Fairford due to build up a deterrent in Europe against the Soviets.

Bombers and tankers from Eaker Air Force Base in Arkansas were deployed from Fairford in the first Gulf War in 1991.

Due to its long runway, Fairford was also used as the test centre for Concorde aircraft until 1977.

And in 2003, B-52 bombers were deployed by USAF from RAF Fairford on raids to Iraq.

BBC security correspondent Frank Gardner said that RAF Fairford is one of a number of "forward operating" bases used by the USAF around the world.

"It's incredibly useful strategically for the US to have this platform," he added.

The USAF's other UK bases include RAF Lakenheath in Suffolk - home to the 48th Fighter Wing operating F-15 and F-35 jets - and RAF Mildenhall in Suffolk, which is mainly a base for US air refuelling tankers.

However, RAF Fairford has the largest runway out of the three sites and an unrestricted load-bearing capacity, which means it can accommodate larger aircraft.

The RAF base is located in the Cotswolds about four miles (6.4km) south of the town of Fairford, which sits along the River Coln, and about 15 miles (24km) north of Swindon.

The village of Whelford lies next to the airbase, with Whelford Road running alongside the eastern end of the runway.

The Cotswolds area is usually quiet, but each July welcomes about 170,000 people for the annual Royal International Air Tattoo (RIAT) which is the largest military air show in the world.

The event was cancelled in 2026 due to the uncertainty over access to RAF Fairford as a result of the conflict in the Middle East.

RAF Fairford remains owned by the Ministry of Defence but is operated by the USAF under agreements between the UK and US governments.

The base regularly hosts deployments of long-range American aircraft, including B-52 bombers and U-2 reconnaissance aircraft, and has played a role in recent operations linked to tensions in the Middle East.

Since 1 March, US heavy bombers have been taking off from RAF Fairford "for defensive missions to destroy Iran's missile capabilities".

Gloucestershire Police said it had received a call about "three suspicious vehicles" travelling towards RAF Fairford at 00:45 BST on Sunday.

Five men were later arrested by its officers near Whelford and have since been released on bail.

Counter-terror police said the three vehicles had been subject to "extensive examination" with support from military and forensic experts.

A large cordon remains in place near the base, with 85 households being told they can return home after an evacuation on Sunday.

You can follow our live page for more details on the story and read a round-up of everything we know about the counter-terror probe.

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