The Dwyryd River Navigation (nprn 91424) consists of some seven kilometres of navigable river and includes the Cemlyn Canal (nprn 91427) and various riverside wharves or quays between Maentwrog Bridge (nprn 24191) downstream to Pont Briwet (nprn 404539). It was last used commercially in about 1873; the principal traffic was slate, but timber, limestone and coal were also carried.
Gelli-grin Quay is situated on the south side of the river; the quay is some 92m long.
B.A.Malaws, RCAHMW, 18 August 2009.