Numbers 1 and 1a and Attached Railings

Numbers 1 and 1A, along with the attached railings, are a house built around 1825, likely designed by Amon Wilds and Charles Augustin Busby. The exterior features painted mathematical tiles and a slate mansard roof, with a late 19th-century cast-iron shop front.

The main elevation faces Old Steine and consists of four storeys with dormers above a basement. It has a two-window range with a three-window range return. The shop front at the corner is framed in a Gothic Revival style, with tracery spandrels on all bays except the entrance. The return features rusticated piers topped with waterleaf capitals. There are flat-arched entrances on both the corner and the return. The principal elevation is designed as a nearly full-height and full-width segmental bay. All windows are flat arched, with floor-to-ceiling first-floor windows that open onto a shallow balcony, which is enclosed by cast-iron railings featuring an anthemion and heart motif. The third-floor windows have projecting sills, and there are storey bands between the first and second floors that align with the sills of the second-floor windows, continuing across the return. The roof parapet is balustraded only on the main elevation. On the return, two third-floor windows are blocked, while the third is filled with a late 19th or early 20th-century canted bay. Many of the sashes retain their original design: 6 x 6 on the first floor, 3 x 6 on the second, and 3 x 3 on the third; the return has 6-pane top sashes on the first-floor windows only. There are stacks on the return and party walls.

The interior has not been inspected. Numbers 1 and 1A, along with Numbers 2-7 Castle Square, form a group.