Originally a stronghold of the Roche family, it appears on the 1655 Down Survey barony map as ‘Crogh’, derived from the Irish word for saffron. The tower later passed to the Creagh family, from whom it takes its modern name. In 1816, Creagh House was built just 20 metres to the south, and shortly afterwards the old tower was fitted up as an appendage to the new residence, though it now stands unoccupied.

The tower measures 8.5 metres north to south and 13.1 metres east to west, with its original defensive features still visible despite 19th-century alterations. Entry is through a ground-floor doorway near the southern end of the east wall, where a pointed arch door surround may be reset from an earlier period. Inside, a lobby covered by an unusually deep murder hole rising to the second floor leads to three doorways: north into an L-shaped guard chamber, south to the main stairs, and west into the principal ground-floor chamber. The tower’s defensive design continues throughout, with mural stairs rising to the southwest corner at second-floor level before continuing as a spiral to the fourth floor.

Each floor reveals different architectural features from various periods of the castle’s history. The second-floor chamber showcases decorated stop chamfers with trefoil patterns and deep window embrasures containing small mural chambers; one plastered over with a segmental vault, the other featuring a window set into the tower’s angle. The third floor contains an attic chamber under a rounded wicker-centred vault, whilst the fourth floor, accessed through a narrow passage, includes a garderobe chamber and a main room with double ogee-headed windows. Though the crenellations have long since disappeared, projecting stones at the southeast and southwest corners suggest corner bartizans once crowned the tower. A rectangular chimney stack projects from the west wall, and the south wall, standing higher than the others, contains an inaccessible mural chamber at its top, its window lights still visible from outside.