Bullock Castle can be dated to about 1150 from the use of curved pointed arches mixed with the older round arches. The warrior's head high up on the outer wall also helps, by the style of helmet, to date the building.
The castle is oblong with a tower at each end, and the archway under the western tower was probably used to pass from one court to another within the boundary walls of the castle. Inside the main door and inner porch is a large barrel-vaulted room originally used for the storage of grain,fish and other goods. A spiral staircase ascends to a series of rooms. On the way up a room on the left may be examined for its sturdy roof construction.