RAF Lakenheath is located 70 miles from London and 25 miles from Cambridge and the largest U.S. Air Force-operated base in England. Whilst it is not accessible to the public, the nearby Lakenheath Fen, a large RSPB wetland reserve with a visitor centre is accessible. The RSBP has converted an area of arable land and Lakenheath Fen now supports reed warblers, sedge warblers, bearded tits and marsh harriers; bitterns have also been seen. The village of Lakenheath is also close by and lies on the border between the Cambridgeshire Fens and Breckland in Norfolk.