Archaeological surveys have traced the outline of this defensive perimeter, which originally enclosed an area roughly 50 metres from north to south and 35 metres from east to west. The most substantial surviving section begins about 4 metres south of the tower house’s southeast corner; a stretch of wall approximately 30 metres long, standing 1.5 metres high and a metre thick, that extends eastward before terminating at what was once a corner tower.

This 3-metre square corner tower still shows traces of a garderobe chute on its eastern side, a reminder of the practical considerations of daily life in a fortified residence. From here, a low grassy ridge continues northward for about 50 metres, marking where the bawn wall once stood and leading to the site of what appears to have been a second rectangular corner tower. Recent excavations led by Dr Eric Klingelhofer in the 1990s uncovered the remains of this northern tower, along with other intriguing structures that shed light on the castle’s evolution.

Klingelhofer’s work revealed evidence of a structure attached to the southeast corner of the tower house, which he identified as an Elizabethan parlour, suggesting later modifications to the medieval fortress. Along the southern bawn wall, his team also uncovered a rectangular building that appears to have been a medieval hall, indicating that Kilcolman was more than just a defensive structure; it was a complex of buildings serving various domestic and administrative functions. These discoveries, documented in the Archaeological Inventory of County Cork, paint a picture of a site that evolved over centuries, adapting to changing architectural fashions and the needs of its successive occupants.