Stanley Baker and Ursula Andress' characters enjoy a picnic on the site of Wraysbury Reservoir which was in the process of being constructed to serve London. It was completed in 1970.
The taxi driver who takes David Warner to the airport was played by Johnny Briggs who was four years away from his most iconic role, Mike Baldwin, on Coronation Street (1960).
Aircraft present at Heathrow include Vickers Vanguard (BEA) and Vickers VC10 and Boeing 707 (BOAC).
The grand monument visible in scenes at the front of the 'National Metropolitan Bank' (on the corner of Grosvenor Crescent and Grosvenor Place in London) is the Wellington Arch.