This lock has unusual curved gates. The GNR line went right over the top of the lock but it was removed after the closure of the railway in 1963. The lock was built without parliamentary sanction (not in the Act). {1} Pound lock on the fen drains constructed by John Rennie between 1802-1812, altered in 1848 when the GNR Lincolnshire loop line was constructed. For the full description and the legal address of this listed building please refer to the appropriate List of Buildings of Special Architectural or Historic Interest. {2}{3}{4}