Y Crwys Independent Chapel including boundary railings and piers

This is a large, eclectic chapel with round-arched detailing, dating from the 18th century and carrying group value through its significant architectural and historical contribution to the area. The front façade is built of rock-faced ashlar masonry, laid in courses with snecked stones, with dressings in Bath stone. The side and rear elevations are rendered, and the roof is covered with slate, featuring a tile ridge. A large, plain vestry addition, also rendered, extends from the rear. The front façade is slightly returned on each side. The window frames on the front and left side have been replaced with uPVC.

The façade is divided into three sections, with the central part slightly projecting. This central section contains three entrance doors and a large, complex round-arched window above, set between pilasters. Tall, round-headed windows are recessed on either side. The large, multiple window is the highlight of the design, comprising a central round-headed light, two smaller windows on each side, two rows of three smaller windows below, and a halo arch encompassing five circular lights above. There are three courses of sill stonework, interrupted by a small, pediment-like detail above the central door. A string course runs to the springing line of the two outer windows. The three doors have plain arches supported by Gothic capitals, with the abaci having a thin string course extending underneath, where the masonry is slightly battered. A decorative coped gable sits above, featuring acroterion-like details on the corners, apex, and pilasters, with a shallow blind arcading between the pilasters, culminating in a finial at the top. The door arches are inscribed with the name "CAPEL ANNIBYNOL Y CRWYS" in incised letters.

The side elevations feature single gallery windows above pairs of lower windows, all round-headed. Rectangular sash windows are present on the vestry.

The chapel is entered via a plain vestibule lit by clerestory windows taken from the lower lights of the central front window. The interior showcases a hardwood and pitch pine pulpit within a round set fawr, altered during a period of enlargement. A gallery, completed at the same time, wraps around the chapel. Seating is arranged in four blocks with two passageways, and the side pews are angled towards the pulpit. The gallery seating follows a similar design. The gallery front is supported by nine cast-iron columns, with a colourfully painted cast-iron openwork frieze above painted boarding, and a plain handrail above. A section of the gallery behind the pulpit has been dropped, providing additional seating and an organ loft. The organ, a two-manual instrument by Blackett and Howden of Swansea, is recessed within an elliptical-headed opening that breaks through the dentilled cornice. The elliptical-section ceiling is divided into rectangles via shallow ribs. The pulpit is symmetrical, featuring canted sides and a dropping section of handrail leading to winding stairs on each side. Carvings of floral and agricultural scenes are in high relief on the large panels with arched heads, supported by black colonnettes. Memorials include a list of ministers dating from 1689, a memorial to E J Long, choirmaster, 1946, and a bronze memorial to those who fell in the 1939-45 war.