This subrectangular heap of stones, reaching just over 1.5 metres at its highest point, is all that’s left of what was once a significant stronghold in medieval Ireland. The site’s uneven surface hints at the substantial structure that once stood here, though many of its dressed stones have long since been carried off for other building projects.

The castle’s history stretches back to at least the 15th century, when Lisdalon served as an important centre for the O’Kelly clan, one of the powerful Gaelic families who controlled much of Connacht. By 1585, the castle was still notable enough to warrant listing in official records, and its strategic importance continued into the turbulent 1590s when Sir Richard Bingham, the English governor of Connacht, maintained a garrison here as part of his efforts to control the region. The castle appears on the Strafford map around 1636, suggesting it remained standing well into the 17th century, though interestingly, no land at Lisdalon was forfeited during the Cromwellian confiscations of the 1650s.

Today, visitors looking for traces of the castle’s former glory might have better luck at nearby Sandfield House, built roughly 180 metres to the west-northwest. The builders of this later house recycled quoinstones from the castle ruins, and various other architectural fragments from the medieval structure can still be spotted there, giving a tangible connection to the fortress that once commanded this corner of Roscommon.