The one at Brenormore in County Tipperary was reportedly brought low not by the passage of centuries or the collapse of its roof stones, but by a fox. When a writer named Keatinge visited the site in the late 1850s, he found it already in a state of ruin and asked his local guide for an explanation. The answer was straightforward: the Tipperary hounds had pressed a fox so hard that the animal had gone to ground inside the souterrain, and the subsequent digging-out had left it wrecked. Keatinge, apparently satisfied with this account, recorded it for posterity.

The souterrain sits within the western side of a ringfort enclosure, the kind of circular earthen enclosure that was a common feature of the Irish countryside from roughly the fifth to the twelfth centuries, used as farmsteads and defended homesteads. What remains today is a linear depression, open to the east, running roughly eight to nine metres in length depending on which side you measure. Low earthen banks define the passage to the north and south, and what appear to be traces of stone corbelling, a technique in which stones are laid in overlapping courses to form a roof, are still visible. Loose stones found in the ditch of the enclosure nearby may once have formed part of the same structure. A second enclosure lies about 360 metres to the south, suggesting this was once a landscape with more going on beneath the surface than is immediately obvious now.