The Tennant Canal lock into the Prince of Wales Dock at Swansea Docks together with 300m or so canal cut behind it, were superseded by a new cut and lock into King's Dock. The truncated 'stump' of the old cut is still visible on the 3rd edition OS 25-inch plan after the new cut had been constructed. The cut into Prince of Wales Dock is clear on the 2nd edition plan, passing close by the Port Tennant Copper Works on one side and the Tennant Wharves on the other at the dock's edge. The new cut was out of use by the mid-twentieth century having given way to new developments. Although these remains are no longer visible the canal and lock sub-structures will be intact beneath these later structures.

David Leighton, RCAHMW, 29 July 2010