Gloucestershire has strong connections with the Battle of Britain
The Battle of Britain was the German air force's attempt to gain air superiority over the RAF from July to September 1940.
Their ultimate failure was one of the turning points of World War Two and prevented Germany from invading Britain.
But did you know about Gloucestershire's involvement in the Battle of Britain?
No. 501 (County of Gloucester) Squadron, which was based at RAF Filton near Bristol, flew defensive missions in World War II, and was the only squadron to fight from the Battle of France in May 1940 to the end of the Battle of Britain, without being rested.
Bill Hickman, from Frampton on Severn, who is Chairman of the 501 Squadron Association, said he is proud of the part they played 70 years ago:
"501 squadron operated as part initially of the Biggin Hill wing from Gravesend, and then later in the battle they switched to Kenley which was the Croydon wing.
"They fought from there right the way through the Battle of Britain right until December before they came back home to Filton.
"Squadrons were rotated but 501 Squadron, along with a couple of others, were not rotated because they were felt to be too important to 11 Group."
Other Gloucestershire connections to the Battle of Britain are the Hurricanes of 87 Squadron and the Spitfires of 92 Squadron, both of which used the airfield at RAF Bibury for periods during the battle.
A detachment of Hurricanes from 87 Squadron flew in from their base in Exeter on 7 August, 1940.
Pilots from the Squadron were billeted in Walton House and the Red Lion pub in nearby Northleach.
A blue plaque commemorating the fact was erected in 2005.
Pilots from 87 Squadron were billeted at Walton House in Northleach
The Hurricanes of 87 Squadron were replaced by a detachment of Spitfires from Wales in August 1940.
Just two hours after they had arrived a German bomb was dropped killing an airman and destroying one of the aircraft.
No. 92 Squadron left Bibury in September 1940 to go to Biggin Hill, to be replaced again by 87 Squadron, which remained at Bibury until December 1940.
During the Battle of Britain RAF Bibury was little more than a grass field and a few buildings. It wasn't until later that the hangers and mat runways were built.
Iconic aircraft from WWII will take to the skies above Cotswold Airport for the Battle of Britain Airshow this weekend on 18 and 19 September as part of the 70th anniversary commemorations.