Moriah Calvinist Chapel

The Moriah Calvinist Chapel, built in 1855, is a distinctive example of Nonconformist architecture. It was constructed for the Methodistiaid Calfinaidd (Calvinist Methodists). The front elevation is imposing, featuring an Art Nouveau style pediment faced in buff terracotta. The return and rear elevations are constructed from a distinctive knapped black rubble-work. The roof is slate, with tiled crestings.

The entrance front has a strong design with polygonal angle turrets topped by cupolas. These have engaged bulbous shafts carrying domed roofs and finials, and the central pediment is also surmounted by a finial. The central entrance has paired panelled doors within a shallow segmental arch with a hoodmould. Similar moulded hoodmoulds define the flanking two-light windows, the large four-light window above the doors, and the three-light windows on either side. Further above, an oculus is contained within a small, decorative surround. Horizontal articulation is achieved through moulded string courses on the angle turrets, aligned with the transoms of the first-floor windows.

The return elevations feature two-light mullioned and transomed windows in terracotta, each with a shallow arched head and hoodmould. Similar windows, paired, are found in projecting transepts to either side. A slate plaque in the apex of the south transept bears the inscription "ADDOLDY / Y / Methodistiaid / Calfinaidd / Adeiladwyd 1855." A gabled rear projection includes a small circular light in the apex, while flanking outshuts have segmentally headed, four-pane horned sash windows. A rear door is located within the south outshut, and a boiler house entrance is in the rear wall of the north outshut.

The main entrance leads into a full-width lobby, situated within the body of the chapel, with doors on either side leading into the main chapel space. The floor is raked slightly down towards the set fawr (main area) and pulpit, which are positioned against the opposite wall. The chapel is furnished with 32 rows of pews, with additional rows extending into the transepts. Doors and the central window from the lobby have leaded lights containing stained glass in an Art Nouveau style. This style of glass is also found in the main window above the lobby and in the small circular light above the organ loft. The internal walls are lined and rendered to imitate ashlar. The ceiling is coved with a cornice, followed by a boarded border divided into two main panels by plasterwork rosettes and angles. These panels contain large central roses with wreathed plasterwork detail, and inset fretted woodwork. The set fawr and pulpit have a turned rail and panelling in a Neo-Elizabethan style. A shallow arched recess is situated at the rear of the pulpit, originally intended for the organ. A door to the left of the set fawr provides access to a staircase leading to the organ loft, while a door to the right leads to a vestry, toilet, and a rear door. The vestry includes a small cast iron fireplace in the southeast corner.