The final stretch of the main Cambrian Coast Line from Barmouth to Pwllheli was completed in 1867 and Pont Briwet or Pont Briwfad toll viaduct was constructed as part of this scheme to carry the railway as well as a road over the Afon Dwyryd. It is of timber construction with a metalled carriageway and the railway is on the west side. There are substantial cross-framed supports and plain metal railings. The viaduct marks the lower extent of the Dwyryd River Navigation (nprn 91424).
B.A.Malaws, RCAHMW, 18 August 2009.