Until the late 19th century, when Ballyteige Lough (known as Mablen Haven in the 1600s) was reclaimed, the castle stood on the eastern edge of this body of water with the shore just 150 metres to its west. Today, the castle complex sits on level ground, its strategic coastal position less obvious to the casual observer.

The fortification consists of a tower house positioned at the southeast corner of a rectangular bawn, or defensive courtyard, measuring roughly 29.5 metres north to south and 22.5 metres east to west. The southern wall of the bawn stands an impressive seven to eight metres high and features a wall walk with musket loops for defence. Though an 18th or 19th century house now occupies much of the eastern side north of the tower house, substantial portions of the original defensive walls remain on the western and northern sides, standing at 3.8 and 4 metres respectively. The original entrance gateway in the south wall, about three metres wide and 3.4 metres high, is now blocked but still shows traces of the wicker centring used in its construction. This entrance was protected by machicolation just west of the tower house, with access to the wall walk via stone steps projecting from the inner face of the southern wall.

Two circular towers add to the defensive capabilities of the complex. At the northwest corner stands a four storey tower, approximately nine metres high with an internal diameter of 2.3 metres, featuring a base batter and corbelling over the first floor. Its ground floor opens to the bawn, whilst the second floor is accessed via a doorway from the wall walk, with a newel staircase rising to the third floor and formerly to the now destroyed battlements. The northeast corner houses another circular tower, at least three storeys high and about seven metres tall with an external diameter of 5.2 metres. This tower contains a particularly interesting feature: a circular stone lined well with four steps leading down to it, whilst a newel staircase built into the wall thickness provides access to the upper floors, each furnished with defensive slit windows.