Noon's Hole (Irish grid ref H12684431) lies about 5 km northwest of the centre of Boho, in the townland of Old Barr in the parish of Devenish, County Fermanagh, close to the border with Boho parish. The cave is under part of the escarpment on the east side of the Glenade Sandstone uplands. At 81 m (266 ft), this pothole was thought to have the deepest shaft in Ireland, but this honour was passed to the near-by Reyfad Pot, which contains an entrance shaft of 88 m (289 ft). The continuation of the cave system (incorporating the Afternoon Series and High Noon's) contains 3.7 km (2.3 mi) of passage, and it connects to the resurgence at Arch Cave through three cave dives, making this system the 8th deepest in Ireland, at 108 m (354 ft). Noon's Hole used to be called "Sumera", meaning abyss, but gained notoriety and the new name of "Noone", after a notorious murder took place there.