This was the main surface incline of Cwmorthin Quarry, running from Floor 6 down to the Mill Level close the the Cross Mill (NPRN 408419). There was a further short incline from Floor 8 to Floor 6 on the same alignment. Bridges at the levels of Floors 2, 3, 4 and 5 carried tramways to the terraced tips on the south side of the incline (NPRN 408416), whilst junctions connected the working areas to the north at each level, allowing slabs to be lowered to the mills. The abutments of another bridge near the bottom of the incline marked the site of the early road up the valley. The drum house on Floor 6 still had its drum in place in the mid-1980s.
By 2008 the bed of the incline had been totally destroyed by recent reworking of the tips, and the site was marked by a furrow amongst the waste.
W J Crompton, RCAHMW, 17 December 2008.