This roughly square tower house, measuring about 6.4 metres east-northeast to west-southwest and 6 metres north-northwest to south-southeast, was likely constructed shortly after 1621/2 when George Calvert received a substantial grant during the Plantation of Longford. His holdings included ‘the castle, town and lands of Ulfeede’, along with 295 acres of arable land and 272 acres of bog and woodland, transforming this medieval fortification into a Plantation-era stronghold.

The three-storey structure showcases the practical building techniques of its time, with walls of roughly coursed limestone reaching 2.1 metres thick, reinforced by alternating quoin stones of cut limestone at the corners. The ground floor features a remarkably intact barrel vault soaring to 3.85 metres high, where you can still spot evidence of the original wicker centring used during construction. This vaulted chamber, measuring just over 3 metres square, was accessed through a doorway in the now-destroyed west wall that connected to the earlier castle’s interior. A mural staircase in the southwest angle provided access to the upper floors, whilst a single narrow window in the south wall offered the chamber’s only natural light.

Today, only the east wall survives completely intact, along with sections of the adjoining north and south walls. The first floor once featured a window in the centre of the east wall, now broken out, with a doorway in its north embrasure leading to another mural staircase in the northeast angle. Above the first floor, a vaulted loft space separated the lower levels from a larger second-floor chamber. Remnants of the original curtain wall still extend from the north and west walls, serving as a bawn wall that would have enclosed and protected the castle grounds during the turbulent years of the Plantation period.