These poorly preserved remains may be the same structure as Walterstowne Castle, which appears on the Down Survey map of Drumraney parish positioned north of ‘The Highway from Athlone to Dublin’. Historical records from 1611 mention the site as part of Robert Dillon of Cannorstown Castle’s estate, describing it as a ‘ruinous castle’ within the townland of ‘Waterstown alias Ballyvater’, alongside 30 messuages and 30 gardens.

What remains of the castle today is frustratingly fragmentary; thick vegetation obscures much of the upstanding fabric, making detailed examination nearly impossible. The most substantial surviving element is a portion of the north wall, roughly five metres long and standing between 1.75 and 2 metres high, which connects to the southwest corner via a more recent drystone wall. The structure has been heavily robbed of its facing stones, with all the inner facing and much of the outer façade stripped away, leaving no dressed stonework visible.

Archaeological surveys from the 1970s recorded that the castle sat within a circular enclosure, defined by an earth and stone bank set on a steep scarp to the northeast, north and west, with remnants of stone facing still visible in places. The south and southwest sides were bounded by a natural rise in the terrain. Today, however, only the faintest traces of this defensive enclosure can be detected in the field, and the old field banks that once extended from the southwest perimeter have completely vanished, leaving visitors to imagine the castle’s original defensive layout.