51, 53, 55 North Castle Street, Edinburgh

51, 53, and 55 North Castle Street in Edinburgh are a pair of classical houses built between 1792 and 1794. The buildings are three stories high with a basement and attic, featuring nine bays and flats above. They are constructed from cream sandstone ashlar with polished dressings. The basement and second floor have a droved finish, while the ground floor displays V-jointed rustication. The first floor is polished with a band course above, and there is an eaves cornice. The southern corners have long and short quoins. The outer bays are united as a pair of bows, with doors to the central three bays; the right bay is slightly broader. The central door has a six-pane rectangular fanlight above it, and the flanking doors are arched with radiating fanlights, with the right door being recessed. There are piend-roofed bipartite dormers, along with a further garret dormer and skylights.

The gable on the largely blank rubble wall has windows at the center, while the rear elevation is a four-story, four-bay structure made of rubble.

The buildings feature timber sash and case windows, mostly with 12 panes, although some have plate glass. The roof has ashlar coped skews, a rendered stack to the south, and a stone mutual stack to the north, covered with grey slates.

The interior of No. 55 was largely refurbished in 1995 and was not seen during the inspection.