It took satellite imagery to formally identify it. A cashel is a type of ringfort defined by a stone rather than an earthen boundary wall, typically associated with early medieval settlement in Ireland, and this one at Boola measures around 30 metres north to south and 32.4 metres east to west. The wall itself, between 2.55 and 2.7 metres wide, survives only as foundations, most legible along the southern and western arc where the stonework is clearest. Elsewhere it has sunk into the turf. The entrance, nearly three metres wide, faces the northeast.

The site was identified and reported by Anne-Karoline Distel working from DigitalGlobe satellite imagery, with corroborating detail visible on Google Earth from January 2018. The wall is built from small boulders, some barely 22 centimetres high, others closer to 54 centimetres, giving the construction a rough, gathered character consistent with a working upland site. Inside the enclosure, set within the northwest quadrant and set back roughly 3.8 metres from the inner wall face, there is a slightly raised oval platform measuring about 10.4 metres by 8 metres, sitting just 17 centimetres above the interior ground level. Its purpose is not stated, but such interior platforms within cashels are sometimes associated with the footprint of a former structure.

The surrounding landscape adds to the site's quiet strangeness. Turloughs, seasonal lakes that fill and drain through karst limestone, sit at the base of the hill to both the northwest and southeast. The views open up considerably toward the south and west, with Borrisnoe Mountain visible to the southwest and Black Hill to the east-southeast. Later field boundaries have clipped the northern edge of the enclosure, and scattered boulders to the east and southwest of the cashel may well have been robbed from its walls to build those very boundaries, a common fate for upland stone monuments that were never entirely forgotten, only slowly dismantled.