Clue: 15's terminal way to fill Ely cathedral post, maybe (9,6,7)
Answer: FENCHURCH STREET STATION
Explanation: Definition: 15's terminal
STREET (way) in FEN CHURCH (as Ely cathedral might be described) + STATION (post) – one of the four stations in Monopoly (I spent far too long trying to justify LIVERPOOL STREET.. here)