Stranraer Castle

Stranraer Castle, built around 1510, is a three-storey and attic, three-bay L-plan tower house with an advanced stair tower on the northwest and a caphouse. An attic addition was made around 1600, with the north and south walls built on the original parapet. The building underwent remodelling in 1821 when it was converted into a town jail, which included the addition of arched windows to the upper two floors to provide light for the cells and access passages. The structure is built of rubble with ashlar dressings, featuring red sandstone quoins, long and short surrounds to openings, and a castellated parapet.

The north (entrance) elevation has a central entrance with a timber door and an empty panel frame above. There is a small opening to the right, a small opening at the first floor, and single windows at the second floor and attic. A splayed gunloop is located at the ground level in the left bay, with a small opening above it and single windows at the first, second, and third floors. A birdcage bellcote sits atop the stack at the parapet, and there are two small windows in the stair tower on the outer right.

The west elevation features regular fenestration in the stair tower and at the center, although the attic window on the second floor has been infilled. There are small flanking openings beside the center window at the first floor.

On the south (rear) elevation, there is a central single window at the first floor, three single windows at the second floor, and three pairs of windows in the attic.

Inside, the ground floor contains two tunnel-vaulted rooms, with gunloops in the south and east walls of the eastern room and a recess in the south wall of the western room. Off the turnpike stair to the left is a narrow room, likely a private chamber. The large vaulted room on the first floor has a fireplace in the north wall that has been reduced in width. A narrow room on the second floor was converted into a passage during the 1821 remodelling to serve two cells to the south, with a third cell accessed directly from the stair. All cells feature tunnel-vaults and iron-plated doors. A passage leads to the attic, which contains two tunnel-vaulted cells, and there is stair access to the flat roof.