But that curve in the ground is likely the ghost of something far older: a low, broad earthen bank that may be all that survives of a 6th-century monastic enclosure. The place is Rahugh, whose Irish name, Ráith Aodha, means the ringfort or enclosure of Aodh, and the enclosure in question may well have defined the boundaries of a monastery attributed to that same Aodh, known in English as Hugh, some fifteen centuries ago.

Aodh of Rahugh was, according to tradition, the son of Cormac Breac of the Cinéal Fiachach of Moycashel, with his mother Eithne coming from the Múscraighe Tíre in Ormond, the area now known as North Tipperary. He is said to have been born in the nearby townland of Killare and his cult extended well beyond Westmeath: he is patron of Killare Church and also of a church at Slieve League in County Donegal. His feast day was observed on multiple dates, principally the 28th of February, though the 4th of May and the 16th of November were also marked, with one 19th-century source recording it on the 10th of November. Into the 19th century, a pattern, the traditional Irish gathering of prayer and community at a sacred site, was still being held at the holy well dedicated to him on the 2nd of November. That well lies about 210 metres to the south-south-east of the enclosure, and an early Christian graveslab known locally as the Headache Stone, also associated with St Hugh, sits roughly 160 metres to the south-west.

The site today holds the ruins of a medieval church at the centre of the graveyard, itself enclosed partly by a post-medieval stone wall and partly by the older earthen bank. A visitor writing in 1896 found the place in considerable disorder, describing tombstones lying two or three deep within what he called a circular cashel, the Irish term for a stone-walled enclosure. That observation, combined with the oval outline of the graveyard, led later researchers to identify the site as an Early Christian ecclesiastical enclosure. A rectangular annexe was added at some point to the north side of the enclosing bank, incorporated into the later stone wall. The whole complex sits on a gentle rise with open views across the surrounding countryside, which gives some sense, at least, of why someone chose to build here in the first place.