Coe Fen is the name of the small fen on the outskirts of Cambridge, and is crossed by The Fen Causeway, one of the major routes into the city. Fronting onto The Fen Causeway and almost adjacent to Coe Fen is The Leys School, a prestigious independent school. Ken Naylor was music master and later Director of Music at Leys School from 1953-1980, and this will no doubt be the inspiration to his choice of name for this fine tune.
Oliver L. Shaw and The Enchiridion (accessed online)