The Nant Francon Roads were built in about 1791 by the first Lord Penrhyn to extend the road along the eastern side of the Nant Francon valley from Port Penrhyn (NPRN 306314), past the quarry (NPRN 40564), to a hotel at Capel Curig. The road was also intended to be a possible through route, although in 1819 Telford's road (A5) was opened on the western side of the valley.

Source: David Gwyn & Merfyn Williams (1996) `A Guide to the Industrial Archaeology of North West Wales?. Association for Industrial Archaeology

Claire Parry, RCAHMW, 14 November 2011.