Though absent from the official castle lists of 1570 and 1574, local historian Twigge recorded that this stronghold, known as “Tamhnach”, was constructed by Mahon MacNamara, son of Sean MacNamara. The castle appears to have been a relatively short-lived structure; whilst Frost noted in 1893 that it belonged to the MacNamaras in 1580, its absence from a 1683 deposition suggests it had likely been demolished by the late 17th century.

Today, visitors to the site will find an oval platform covered in grass and scrub, measuring approximately 18 metres from north to south and 6 metres from east to west. The platform is defined by a scarp that rises between one and three metres high, offering the only remaining physical evidence of the castle’s footprint. These modest remnants hint at what would have been a typical Irish tower house of the period, built during the tumultuous years of the 16th century when such fortifications dotted the Clare landscape.

The site’s history has been documented through the work of local historians including Michael Moore, Leo Morahan, Risteárd Ua Cróinín and Martin Breen, whose unpublished report on the castles and tower houses of County Clare provides valuable insights into these often-overlooked monuments. Though Toonagh Castle may lack the grandeur of better-preserved Irish fortifications, its remains offer a tangible connection to the MacNamara clan’s influence in medieval Clare and the volatile political landscape that saw many such structures rise and fall within just a century or two.