The Arrouaisians were a reform congregation that followed the Rule of St Augustine, and their houses were among the more disciplined expressions of religious life in medieval Ireland. That a community of such women was established in this quiet corner of Connacht, and then largely forgotten by history, gives the site its particular quality of quiet strangeness.

The convent, known as Termonkeelin, was founded after 1223, most likely by nuns drawn from existing communities at Derrane and Roscommon. Its origins, however, reach back considerably further in tradition. The site is associated with St Caolainn, sometimes described as a disciple of St Brigid, and the holy well of Tober Caelainn lies about 450 metres to the west, suggesting a continuity of veneration that long pre-dates the medieval foundation. By 1306 the convent appears in the ecclesiastical taxation records under the name Ternumkrum, and it later became a dependency of Kilcreevanty in County Galway. What remains on the ground today is a raised rectangular platform, roughly 25.5 metres east to west and 15 metres north to south, defined by grass-covered spreads of stone. Some of those stones may be original wall fabric; much of the spread is likely field clearance dumped over centuries. The field immediately to the north carries a tradition of use as a children's burial ground, the kind of informal, unconsecrated space that communities across Ireland set aside for unbaptised infants. A standing stone sits about 100 metres to the south-east, and an old road once ran southward from the church to Termon More, threading these sites into a now barely legible sacred landscape.