Built sometime between 1550 and 1570, this four-storey structure measures approximately 7.5 metres by 6 metres, making it one of the smaller fortified residences of its type in the region. The castle’s walls, constructed from locally sourced limestone, vary in thickness from 1.2 to 1.5 metres, providing both defensive capability and structural stability. Despite its relatively compact footprint, the tower house follows the typical design principles of its era, with a vaulted ground floor that likely served as storage, whilst the upper floors contained the main living quarters.

The castle’s defensive features reflect the turbulent nature of 16th-century Ireland, when local conflicts and cattle raids were commonplace. A murder hole positioned above the entrance allowed defenders to attack anyone attempting forced entry, whilst narrow arrow loops provided covered positions for archers. The spiral staircase, built into the thickness of the wall, winds clockwise; a deliberate design choice that gave right-handed defenders ascending the stairs an advantage over attackers coming up. Interestingly, traces of a bawn wall, a defensive courtyard enclosure, can still be detected around the castle, though much of this outer fortification has been lost to time.

Today, Drimmeen Castle remains in reasonable condition for an unrestored tower house, though ivy growth threatens the integrity of the upper walls and several sections of masonry have collapsed. The structure retains many original features including stone corbels that once supported wooden floors, a garderobe (medieval toilet) chute, and remnants of window seats carved into the deep embrasures. Local tradition associates the castle with the O’Brien clan, who dominated this part of Clare for centuries, though documentary evidence for specific occupants remains scarce. The site offers visitors a glimpse into the everyday realities of minor Irish nobility during the late medieval period, when such tower houses dotted the landscape as symbols of local power and centres of agricultural estates.