# Ogof Agen Allwedd

- **Country:** United Kingdom
- **Access:** [https://cambriancavingcouncil.org.uk/MLCMAC.html Mynydd Llangatwg Cave Management Advisory Committee]
- **Length:** 32.5 km
- **Survey:** [https://chelseaspelaeo.org/caves/agen-allwedd Chelsea Spelaeological Society]
- **Geology:** Limestone
- **Hazards:** Main streamway flood prone
- **Language:** Welsh
- **Location:** Llangattock escarpment, Wales, United Kingdom
- **Registry:** [https://www.cambriancavingcouncil.org.uk/registry/ccr_registry_view.php?ID=809 Cambrian Cave Register]}}
- **Discovery:** Initial discovery 1949, breakthrough in 1957.
- **Translation:** Keyhole Cave
- **Photo Caption:** The gated Ogof Gam entrance to Agen Allwedd cave.
- **Entrance Count:** 1

Ogof Agen Allwedd or Agen Allwedd, is, at , one of the longest cave systems in Wales, and the longest cave system on the Llangattock escarpment.

![Photo of Ogof Agen Allwedd](https://upload.wikimedia.org/wikipedia/commons/a/a7/Agen_Allwedd_Cave_-_geograph.org.uk_-_609736.jpg)

**Source:** https://en.wikipedia.org/wiki/Ogof_Agen_Allwedd (Wikipedia, CC BY-SA)