Entrance Lock To The Tamar Manure Navigation

The entrance lock to the Tamar Manure Navigation is located at the southern entrance of the navigation, with remains of the entrance lock found at the northern end. It is dated to 1798, although it is believed to have been constructed in 1808. The lock features granite ashlar walls and includes one pair of wooden lock gates equipped with iron winding gear for the sluices.

The lock basin measures approximately 25 metres in length, with the gates situated at the southern end. The granite ashlar walls are splayed back at each end of the lock basin, and the lock gates are partially collapsed. There is a granite mooring post at the south end, and the iron winding gear for the sluices is still present. At the northern end of the canal, the granite ashlar walls remain, but there are no gates.

The canal was originally built for the Tamar Coal Manure and General Mercantile Company and was diverted and shortened by the Duke of Bedford in the early 20th century. It continued to be used for supplying coal to the Gunnislake Gas Works until 1914. The company was liquidated in 1942, and the canal is listed as an Ancient Monument.