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154:, a river whose name translates as 'lightning', commonly explained as a reference to the "flashy" nature of the river, i.e. its rising and falling rapidly in response to rainfall. In 1998 the cave's passageways had been measured as over 2.25 kilometres (1.40 mi) in length. Among the cave's fifteen entrances is the largest cave entrance in Wales and one of the largest in the UK, nearly 20 metres (66 ft) wide and 8 metres (26 ft) high. The cave was used as a
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mud cavern. Challenging elements of the cave interior include the "Wormhole" (a curving crawl tube on the right wall of the main entrance), the "Letterbox" (a rectangular space in the passage) and the "Creek", further inside the cave. There are also two features named the "Washing
Machine", both of which feature large expanses of water.
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Porth yr Ogof is most often entered through the wide main entrance, either using a dry ledge on the left or by wading through the knee-deep river to the centre and right. The second most used entrance is called the
Workman's or Tradesman's Entrance. A passage in the left of this entrance leads to a
182:. The cave is generally wet. White Horse Pool, named after the shape of the calcite deposit on the back wall, is several metres in depth despite the shallowness of the edges, and there are many
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at Porth yr Ogof since 1957, ten of which occurred in the cold, fast-flowing and 7-metre (23 ft) deep
Resurgence Pool at the far end of the cave where the Afon Mellte resurges.
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Porth yr Ogof is now uncommercialised, and is used as a training cave for caving. There are two short
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218:, translated as 'gateway to the cave'. The cave lies in the valley of the
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many years ago, but is not as attractive as more decorated caves such as
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Standing, Peter; Lloyd, Oliver (1970). "Porth yr Ogof, Breconshire".
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Proceedings of the
University of Bristol Spelælogical Society
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222:and is located in a comparatively narrow band of
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198:Porth yr Ogof resurgence in flood conditions
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376:Closed show caves in the United Kingdom
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291:from the original on 20 January 2008
142:, near the southern boundary of the
16:Cave near Ystradfellte, Powys, Wales
285:"Porth yr Ogof – UK Caves database"
233:were mentioned in the writings of
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312:The Secret World of Porth Yr Ogof
150:. It lies on the course of the
229:The cave and its many visible
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178:easily accessible to amateur
361:Tourist attractions in Powys
210:Geological and human history
144:Brecon Beacons National Park
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92:2.25 km (1.4 mi)
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224:Carboniferous Limestone
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310:Farr, Martyn (1998).
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259:"Brecon-Beacons.com"
138:near the village of
265:on 13 November 2013
214:'Porth yr Ogof' is
119:Gateway of the cave
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239:Caves & Caving
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73:51.8006°N 3.5562°W
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35:The main entrance
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371:Fforest Fawr
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293:. Retrieved
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267:. Retrieved
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235:Edward Lhuyd
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140:Ystradfellte
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46:Ystradfellte
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269:13 November
220:Afon Mellte
160:Dan yr Ogof
152:Afon Mellte
115:Translation
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52:Coordinates
355:Categories
295:5 February
245:References
61:51°48′02″N
343:(2): 214.
180:potholers
156:show cave
107:Entrances
101:limestone
64:3°33′22″W
289:Archived
176:potholes
41:Location
231:fossils
97:Geology
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190:Deaths
121: (
89:Length
216:Welsh
184:sumps
148:Wales
134:is a
123:Welsh
44:near
316:ISBN
297:2008
271:2013
146:in
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Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.
