26, 27, 28 Castle Terrace, Edinburgh

11, 13, 15 Cornwall Street in Edinburgh is a corner block building designed by Sir James Gowans between 1868 and 1870. This four-storey structure features an attic and basement, topped with a mansard roof. It has three bays facing Castle Terrace and three bays on Cornwall Street, with a narrow splayed corner bay that includes narrow windows and a battered base.

The building showcases unique detailing, including Moorish influences and polished ashlar stonework. String courses separate the floors, and there are stone bracketed eaves. The windows are adorned with decorative bracketed surrounds, and the lintels of the first-floor windows feature serrated Moorish carvings. The third-floor windows are round-arched and push up against the bracketed eaves below the dormers.

On the Castle Terrace elevation, there are stone steps leading to a basement area at the center. A timber panelled door with a deeply recessed tripartite fanlight is flanked by side-lights with leaded stained glass, all set in a carved surround. The attic features a hooded Serliana. The flanking canted bays have Serliana windows at ground level and tripartite windows with decorative stone mullions above. The steeply-pitched gabled dormers in the attic have stone bracketed eaves and are flanked by smaller hooded dormers.

The Cornwall Street elevation also has stone steps leading to a central basement area. It features a timber panelled door with a round-arched fanlight set in a round-arched glazed doorpiece, flanked by side-lights in a recess with serrated carved decoration in the spandrels. The attic has a hooded dormer, and the projecting flanking bays have Serliana windows at ground level and tripartite windows with decorative stone mullions above.

The windows are made of plate glass in timber sash and case frames, and the roof is covered with graded grey slates. The building has a moulded stone ridge, fluted ashlar stalks with scalloped, bracketed cornices, and decorative octagonal cans with serrated tops.

Surrounding the property is a boundary wall with decorative cast-iron railings on a low ashlar wall, featuring stone piers that mark the corners and entrances.