INFORMATION:

RAF Finmere, Buckinghamshire is situated between Buckingham & Bicester. Either go north out of Bicester on the A4421 or west out of Buckingham on the A421. Where the two roads meet at a roundabout that is the western end of the airfield. There is s Sunday market held on the main runway.

This is the where the control tower is situated -
OS Ref: SP645320
You can use the Ordnance Survey 'Get a Map' and follow the instructions. Copy and paste the map reference.