Fear is the little death.
Silica rock was discovered in these here hills in the 1780s and became a principal component of top quality firebricks. The first tramway was built in 1807, the 'Dinas Fire Brick Co' was inaugurated in 1822 and a brickworks built at Pontwalby. Starting as quarries, the workings soon extended underground and the stone taken through the tunnel to the village. The mines were closed from 1921 to 1930 when a new tramway was built down the river and down the incline ramp or chute. The mines were acquired by 'Richard Thomas and Baldwin', owners of Ebbw Vale steelworks who built the aerial ropeway over the hill. Finally the mine closed in 1964 and after a few years of inactivity the site was cleared in the early 1970s.
Upper Dinas The most extensive mine in the area, and the most recent, is found on the North bank of the Sychrhyd 200m upstream of Bwa Maen, and has three entrances which face the river, and a further ten on the northern side. The triple entrance is to the left of the bridge, and is the mine most frequented by cavers. This is probably the most extensive mine in the area. The upper series is practically a veritable huge chamber where the `Pillar and Stall' method of mining is well illustrated. This large chamber leads towards several alternative entrances in the side of the hill. The large entrance chamber can be followed to the right down dip for a short distance to the flooded section. However, to the left the huge Pillar and Stall chamber leads up dip for some distance only to drop down dip again onto a passage which runs across the whole length of the mine. Above this passage various `entrances' lead to the huge chamber while below is flooded.
Been here three times now with various people and I could quite happily go back again. After a fairly short walk up a rather large hill you drop down into the valley and find the mines. Upper Dinas is the biggest and most impressive of the three on the menu today so we'll start with that first.
Not much more than a very large tunnel really and quite handily is rather close to Upper. One annoying thing is that it is blocked at the east end which cuts off the shortcut back to the car, its also a little flooded. Its been hollowed out a bit on one side of the main passage and theres another lesser passage down to the left which ends in a small lake.
Lower Dinas or Blue Silica Mine
This ones a bit of a walk from the other two and quite small. Most of it is flooded and if you want to se the big chamber youre gonna need waders or a dingy. It gets its name because there is a small calcite flow in one chamber that has been stained blue.
Thanks for looking.