Ogof Nant Rhin

Location
Follow the Heads of the Valley Road from Brynmawr towards Abergavenny. About a mile from Brynmawr there is a large lay-by on the right with a SOS phone in it. Park your car here. Almost in the middle of the lay-by is a place where the fence has been made easy to climb. From here there is a rough path tending downstream that descends into the gorge. This path leads to the cave entrance. The ground is unstable scree and great care should be taken climbing down and up.

Grid reference: SO 21040 12420 or 51.804824N, 3.146587W

Access
Not gated.

Description
The entrance is where a small stream issues about 1 metre above the river. It is a tight, wet, cold, scaffolded, start which is too tight for persons of above average size. After about 2 metres the passage turns 90 degrees right and goes up about 1 metre. There is scaffolding in this corner and care needs to be taken if rocks are not to fall on your back!

Once round the bend and up into the cave propper you are in a hands and knees, sometimes stooping passage which already has a few formations. After about fifteen metres the stream is lost and the passage turns sharp left. This is Aqueous Corner. Continuing for about 5 metres the stream is rejoined and the passage leads into a rift passage, downstream is blocked immediately, upstream is a hands and knees crawl in the Nitty Gritty Mississippi. The rift has many fine formations and is quite high, despite the fact you a forced to hands and knees crawling in a few places. After about 40 metres there is a fine, small rock pool on the right - an aven in the making? Continue another couple of metres and you reach a vertical oxbow. If you go low it is tight and ordinary, it is also raining. If you go high there is a tight squeeze through golden flowstone into Golden Showers, after which you drop back into the bottom of the rift.

Continue until you reach a waterfall. If you want to visit the large Aven d'Oznog with its impressive flowstone column, or visit Ogof Pont Gam turn round and go back the way you came. On the left you will see a limestone 'formation' dropping from the roof, the bottom of which looks like a ships keel cutting diagnolly across the rift. Instead of crawling under, climb up just before the 'ships keel', you will go under a large fallen boulder. Climb back over the fallen boulder and continue under some formations until you are high in a rift. Continue along the rift at various obvious levels. There is a tight place you must climb over a boulder, shortly after there is a long flat out crawl, once this ends the passage turns sharply left and ends, at this point you can climb up into Aven d'Oznog.

If you want to visit Ogof Pont Gam, now is the time to put your harness on because you don't want to be wearing it in the flat out crawl. You should find a rope dropping down at the far end of the Aven.

If you want to go back into Ogof Nant Rhin go back through the hole in the floor. After the flat out crawl the passage allows one to stand again. You are in a rift and very soon there is a boulder in the rift. At this point it looks like the way on is to go high in the rift, but this way on soon becomes too tight. The way on is to go over the boulder and down into the bottom of the rift. From here continue at various levels in the rift until you are high and there are formations. You will hear water in the distance from a waterfall. After passing some formations you will climb over a large fallen boulder. The way on is to go back under the boulder and climb down. The waterfall will be to your right.

Climb up the waterfall and continue along the rift till you come to a junction. To the right is a well decorated passage leading into the Garden of Delights. It is not necessary to enter the Garden - just admire it from the entrance for there is no way on.

Continuing left from the junction one enters a wide high phreatic passage with a large, impressive flowstone column formation. A little further is Empire Bridge and one must climb over several fallen boulders. To the right is Periodic inlet, but there is no way on there. Continue along the stream in a crawl until you reach Distant Voices Aven. At the far side of Distant Voices Aven is another short crawl to a smaller aven. Continue in a longer crawl until the passage widens and turns left. To the right one can climb up a tube past some small formations, or one can crawl on, either way you enter Shaven Aven and meet the mud creatures:-) There is a rope hanging here. The aven has been climbed but it becomes too tight after about 20 metres.

At the far end of the aven a narrow, tight, awkward passage leads to a junction. It it is possible only to turn right at the junction. From here, crawl backwards into a small chamber turning to the right. One can then climb about 1.5 metres up a waterfall - this is Kerplunk - at the top is a tight very short passage that seems to be being dug.

If one re-enters the bedding plane that leads to Kerplunk and carry on, one comes to the Jaws of Death, to the left is a very tight crawl that soon ends, carrying on the passage is tight and turns right, ending in a small chamber. To get back out it best to go back into Kerplunk, then go backwards into Shaven Aven.

History
First explored in 1991. Survey T.Copeland et al 1993, Descent (111)