The 1659 Down Survey parish map of Leny confirms their existence, recording ‘at Ballinilack two Castles & a Bridge upon the River Ighny’, though no surface remains of these fortifications are visible today. Based on cartographic evidence, historians believe one castle stood on the north side of the road crossing the bridge, whilst the second was positioned on the south side; the building later marked as ‘The Bridge House’ on Ordnance Survey maps may have been one of these structures, with an earthwork in a nearby field possibly representing the remains of its companion.

The eastern castle belonged to the Ledwich family for centuries, serving as both their seat of power and a symbol of their status amongst Westmeath’s chief gentry. Christopher Ledwich died in 1406, seized of the Castle of Ballinalack along with fishing rights on the River Inny. When Edward Ledwich died in 1628, his estate inventory reveals the extent of the family’s holdings: one castle at Ballinalack and Grange with 120 acres, plus substantial lands in Carrick, Fulmort, Cappagh, Joanstown, Cullenhugh and Heathland, totalling over 500 acres. The family maintained their prominence as patrons of nearby Tristernagh Abbey and remained influential local figures well into the late 17th century.

The castles witnessed considerable conflict during Ireland’s tumultuous 17th century. In 1642, Parliamentary forces attacked and captured the Castle of Ballinalack during the Confederate Wars, marking a significant blow to the royalist cause in the region. The Ledwich family’s fortunes further declined following their support for the Jacobite cause; James Ledwich of Ballinalack was listed amongst the Irish Jacobites attainted in 1691 after the Williamite victory. These twin fortifications, which had protected this vital river crossing for centuries, ultimately fell victim to the political and military upheavals that reshaped Ireland’s landscape, leaving only documentary evidence and subtle earthworks to hint at their former strategic importance.