The Bute Merthyr Colliery, in Treherbert in the Rhondda Valley, was the first colliery to produce steam coal in the Rhondda valley. A trial pit was dug in 1851, and the colliery was closed in 1926.
In 1849, Marquess of Bute bought the Cwmsaerbren farm from William Davies for £12,000.[1] W. S. Clarke was employed to sink the first trial shaft in 1851. In April 1853 the first seam was struck at a depth of 125yd. A second shaft had been sunk by 1855, when the first coal was produced.[1] Progress was slow because all equipment was carried over rough tracks by horse and cart from the Taff Vale Railway's then terminus at Dinas.