The Dinas incline was one of three gravity-worked inclines on the original line of the Penrhyn Railway, built 1800-1801 to transport slate from the Penrhyn quarries to Port Penrhyn. It went out of use when the railway was realigned to allow steam traction in 1879.
About half-way up the incline was an overbridge carrying a minor road, now widened and straightened at this point. To the north a cutting can still be seen, but the lower part of the incline has been destroyed by construction of a sewage works. To the south the line is visible as a terrace in the field. A ruined wall constructed of large roughly squared stone blocks near the top of the incline may be a surviving fragment of the winding house.
W J Crompton, RCAHMW, 5 November 2009.