New Siloh (Seilo Newydd) Congregational Chapel, including gates and railings.

New Siloh (Seilo Newydd) Congregational Chapel, including gates and railings, is a Grade II* listed building. It features snecked rubble facings with pale freestone dressings, granite shafts, and a slate roof. The chapel has a three-bay open pedimented facade topped with a tall finial and balustraded parapets at the corners. The facade includes corbel tablets, a plain frieze, and a chequered treatment to the pilasters with acanthus capitals. Flanking the arched head of the three-light traceried center window, which has a parchment scroll above, are shafts with capitals below the transom. There are three gabled and finialled doorways set into the rubble wall of the porch, featuring carved tympana, arched doorways, and an acanthus band. The outer bays have tall arched lights with marginal glazing bars, while the seven-bay flank elevations are adorned with giant pilasters and arched windows on two levels. An extension for the organ loft is located over an arched passage.

The chapel is situated on an enclosed platform site with snecked rubble revetments, pyramidical Gothic caps on the piers, and original spear gates and railings.

Inside, the magnificent space accommodates 1,100 people and features a shallow elliptical ceiling with elaborate ribbed panelling, pendants, and pierced roses for lamps. A continuous gallery supported by barley-sugar iron columns has an iron filigree front and moulded floral decoration on the coving, with a clock framed by pillars. The gallery sweeps down above the pulpit, with an organ console located at the rear of the choir benches. The broad organ case displays exposed decorated pipes, and stained glass windows are positioned on either side of the organ. The large polygonal pulpit features relief panels and arcading, with balustraded stairs on each side. The balustrade surrounding the set fawr enclosure has panels with relief decoration. The interior retains its original pitch pine seating on both levels.