This motte and bailey castle, likely built in the 1190s during the Anglo-Norman settlement of Longford, may actually incorporate something far older; a 6th-century mound that once served as the seat of the kings of Teathbha. The site’s Irish name, Liss-ard-abhla, meaning ‘fort of the hill of apple trees’, hints at a more peaceful past, whilst medieval documents refer to it as Incheleffer or variations thereof.

The castle’s impressive defensive layout consists of a steep-sided circular motte standing 9.5 metres high, originally crowned with stone fortifications, surrounded by two crescent-shaped baileys to the southeast. The motte is separated from the inner bailey by a wide, deep fosse that once would have been a formidable obstacle to attackers. The inner and outer baileys are themselves protected by multiple rings of banks and ditches, with the northeastern side featuring a particularly substantial defensive system known historically as ‘the Rampart’, complete with a waterlogged fosse nearly 15 metres wide and almost 4 metres deep. A large piece of masonry at the base of the motte’s fosse may be all that remains of the summit’s stone buildings or perhaps the foundation of a wooden bridge that once spanned the defensive ditch.

The castle’s turbulent history reflects the violent reality of medieval Ireland. In 1210-11, William le Petit invested £6 10s to strengthen Incheleffer’s fortifications, money that proved well spent when Hugh O’Conor attacked the castle in 1224, though not well enough; the entire garrison was killed in the assault. Today, these earthworks stand as the only visible remains of the medieval settlement at Lissardowlan, with cultivation ridges to the southwest likely dating from post-medieval ploughing rather than the castle’s heyday. The poorly drained land to the east and south, which once provided natural defence, now serves as a reminder of why this particular ridge was chosen for such an important stronghold.