An Ráth Rua, the russet ringfort, sits in low-lying boggy land in north Kerry, and its reddish character comes not from folklore or poetic licence but from the ground itself. The local clay here runs red, and that same material was once dug up and fired into bricks. A prehistoric enclosure and a small-scale brick industry share the same patch of earth, which is not the kind of detail that turns up often.

A rath is a ringfort, a roughly circular enclosure defined by one or more earthen banks, typically built during the early medieval period in Ireland and used as a farmstead or defended homestead. This one is univallate, meaning it has a single enclosing bank, which survives to a height of 2.1 metres on the outside and 1.7 metres on the inside, with a base width of five metres. The interior diameter runs to 32 metres. Three gaps punctuate the bank, on the north, east, and south-east sides, measuring five, three, and three metres respectively, each one an access point into the interior. The bank is much levelled in places, worn down by time and the boggy conditions of the surrounding land. Just to the north-west, there is what may be a second, unmarked enclosure, its nature not fully established. C. Toal's North Kerry Archaeological Survey, published in 1995, recorded all of this, noting also the local belief that the name Rathroe derives directly from the red clay underfoot rather than from any later association or individual.