The site consists of a roughly rectangular earthwork measuring about 42.5 metres north to south and 33.5 metres east to west, with earthen mounds at three corners that still contain visible stonework, suggesting collapsed masonry from what was once a formidable bawn. Within the southwest corner of this defensive perimeter, the foundations of a rectangular building can still be traced; an 11 by 6.5 metre structure that was built against the southern and western walls of the fortification.

Historical records paint a vivid picture of what once stood here. The Civil Survey of 1654-6 describes ‘a Castle & Bawne, a bigg thatcht house’ that existed at Garranlea in 1640, owned by Thomas Butler, an Irish Catholic gentleman of some standing. Even earlier documentation from the Ormond deeds mentions an artillerist named Cornelius MacShane O’Meagher who received a pardon in 1560 and may have been connected to this very site. The building foundations within the bawn could be the remnants of either a tower house or that substantial thatched dwelling mentioned in the survey.

The site’s complexity extends beyond the main fortification, with a rectangular annexe adjoining the western side that measures roughly 29 by 23 metres, defined by substantial earthen banks that are particularly pronounced at the southwest corner. The surrounding field contains numerous undulations and earthworks, including a triangular enclosure connected to the southern side of the castle earthwork, suggesting this was once a bustling defensive complex with multiple structures and enclosed spaces. Today, a post and wire fence cuts across the northern portion of the site, which runs along the avenue to the modern Garranlea House, whilst a church stands just 60 metres to the northeast, continuing the site’s long tradition as a focal point of local life.