Visible Remains - info by user SJT

At ST 18450 99250 (the given location of the mine on the referenced NMRS website), a flat area of land (processing area/tram road?), and possible collapsed drifts are visible , along with a backfilled concrete tunnel portal and a spillway, though it is unclear if this is related to the mine.

At ST 18550 99750, (one of the grid references from welshcoalmines.co.uk), also the location of levels marked ‘Islwyn’ on the Coal Authority Map, more remains are visible.

A level at the head of the tramroad discharges orange water, and there are several collapsed adits in the right hand bank of the valley. This was also the location of 2 levels for the earlier Gwrhay Colliery, so I cannot be sure which of the vague depressions in the ground are which!
I suppose these Gwrhay levels are the referenced ‘old workings’ that the Islwyn levels were driven through.

Upon walking past the farm, we were challenged by the landowner, who was very helpful once we explained we were researching mining remains. She pointed out a roadside retaining wall, which apparently relates to a now demolished aerial ropeway to the tip.

Levels commenced by William Barnes in 1918, and driven 700 yards through old workings to access a virgin take in the Mynyddislwyn Seam (SW114).

In 1936, two of his sons were trapped underground by a roof fall for 4 days before being rescued, and shortly after this he sold the mine to E.H. Bennet & Co. in 1937

Nationalised in 1947 into South Western Division No.5 Rhymney Area, when they worked the Lower Mynyddislwyn seam (SW114I), and robbed pillars from workings in the top seam, before closure at the end of 1948.