They also show military personnel who were based at the adjacent airport. The Avro factory produced Lancaster bombers which were used in the legendary “Dambuster” raids. The 70th anniversary of the raids was marked in May 2013, and the importance of the Yeadon factory was highlighted in a parliamentary motion put forward by the then Leeds North West MP Greg Mulholland. The factory, which was built in 1939 alongside what is now Leeds Bradford Airport, covered a million and a half square feet, and was the largest single factory unit in Europe at the time. Called a ‘shadow factory,’ the Avro unit contributed to the aircraft production necessary for the war effort. In order to avoid airstrikes, the roof of the factory was camouflaged with fields, hedgerows, dummy buildings, and even a duck pond. The camouflaging tactics were successful, as the factory was never detected by enemy bombers throughout the war.