Seion Welsh Congregational Chapel

Seion Welsh Congregational Chapel is an Italianate classical building dating from the 19th century. It features a two-storey and basement structure with a three-bay pedimented front, resembling the design of the Bethel Baptist Chapel located further up the street. The exterior is constructed of snecked rubble masonry with painted freestone dressings, including band courses and end pilaster strips that extend to the ground floor. The slate roof has steeper hipped cross roofs over the front outer bays and a cement render chimney stack.

The raised pediment is adorned with a bracket cornice and a blind attic roundel positioned above a broad tripartite central window, which has arched heads and Venetian Renaissance glazing in the center. Below this window is a balustraded apron, flanked by paired giant order Corinthian pilasters set on high bases. The outer bays feature a balustraded parapet and similar windows on the first floor, which are square-headed with bracket cills. The central entrance consists of twin arched and keystoned doorways with panelled double doors, accessed by twin parallel steps that have iron railings over a parapet, terminating in sturdy gate piers. The basement has fixed windows.

The facade extends over the corners by one bay, with cement render side elevations that include small pane sash windows with arched heads on the first floor and a panelled door entrance on the left side.

Inside, the chapel boasts a fine five-bay aisled rectangular galleried interior featuring painted classical details. The plaster ceilings are coved and panelled in the central nave, with acanthus ornamented roses in each bay. Transverse ribs cut through the dentil cornice, supported by Corinthian corbel shafts. The upper storey is arcaded, embellished with keystone and fleuron ornament, and features Corinthian columns and hoodmoulds above the front tripartite window. The raked gallery front is panelled and bracketed, supported by plain Ionic cast-iron columns. A full-height organ case is situated behind the platform, along with a great seat that has balustraded parapets. The entrance lobby contains a coloured glass window, and there is a school room below with plain cast-iron columns.