18, 19, 20, 21 South Bridge, 29 and 31 Niddry Street Edinburgh

This building, located at 30, 31, 32, 33 South Bridge and 45, 47, 49, and 51 Niddry Street in Edinburgh, is possibly designed by Robert Kay and dates from around 1790. It consists of a row of five sections, each with seven bays, primarily featuring three-storey and attic, four-storey, or four-storey and attic Classical tenements that include shops on the ground floor, some of which have been altered. The structure is situated on steeply sloping ground, rising to six and seven storeys at the rear on Niddry Street.

The south elevation, facing Cowgate, has a prominent pedimented gable end that reaches seven storeys and an attic. The building is constructed with ashlar stone, while the rear is made of rubble. Architectural details include band courses, raised cills, and a cornice, along with piended and canted dormers. The shopfronts on the west side (South Bridge) feature fluted timber Ionic pilasters, timber stallrisers, and fascias. The window openings at numbers 19-29 have applied, moulded architraves.

On the east elevation (Niddry Street), there are some round-arched openings at the ground level and occasional Venetian windows on the upper floors. The upper storeys also include three-light pedimented wallhead dormers with gable stacks. The south elevation features round-arched windows on the fourth storey and a pediment with a central lunette window, along with some blank windows.

The windows are predominantly plate glass and twelve-pane timber sash and case, with plate glass used on the ground level. The roof is covered with grey slates, and there are gable and wallhead stacks, along with cast iron rainwater goods.