St Mary's Roman Catholic Church, 59 Sherrigrim Road, Stewartstown, Dunannon, BT71 4DH

St Mary's Roman Catholic Church is a 19th-century church in Gothic Revival style, located on the edge of Stewartstown village, set back from the main road within its own grounds. The building is of cruciform plan, comprising a short nave, transepts, and shallow chancel, with a later tower and spire positioned next to the chancel.

The walls are constructed of hammer-dressed snecked sandstone with smooth sandstone dressings, including block surrounds to windows and a projecting plinth. Diagonal buttresses reinforce the outer corners of each block; those serving the transepts and chancel gable rise to octagonal pinnacles. Some stonework of these pinnacles, at eaves level and above, comprises recent replacement fabric for the original. The roofs are laid with Bangor blue slates in regular courses, and rainwater goods are of cast iron with circular downpipes.

The main visual elevation faces south toward the main road. Here, a central chancel gable is joined to the tower on its right, with both projecting forward from the two transepts which extend to either side. The chancel gable contains a three-light geometrical traceried window with stained glass behind modern storm glazing, topped by a drip moulding with plain block stops. In the gable apex sits a datestone inscribed '1845' within a trefoil surround, and a cusped stone cross surmounts the gable. To the left of the chancel, between it and the transept, a canted bay in two stages contains a small rectangular window at lower level and is roofed by stone weatherings.

The tower is of square plan in two stages beneath a tall stone broach spire. The lower stage contains two Gothic lancets set one above the other. The upper stage holds a two-light plate-traceried opening with louvre boards, set in a Gothic arched surround rising from a single weathering. The tall broach spire above contains a louvred lucarne at its base and an elaborate metal finial and cross at the top. The other faces of both the upper tower stage and spire mirror this face, though the lower stage on the east face is blank. The transepts each contain a simple Gothic arched lancet with drip moulding.

The west elevation comprises the west transept gable projecting forward from the nave. The transept gable has diagonal buttresses rising to octagonal pinnacles, with some stonework recently replaced. A central doorway contains a pair of rectangular ledged timber doors with a Gothic arched plate glass fanlight in a chamfered arched surround with drip moulding, approached by a stone step. Above is a single-light window matching the south transept. The north face of the transept is blank. The west elevation of the nave contains a tall Gothic arched lancet without drip moulding.

The main entrance originally faced north at the centre of the nave gable, but a modern extension has created a lateral porch across that gable with two new entrances approached from the east and west sides. Two other entrances in the transept gables, facing east and west, remain in use. The north gable of the nave is largely covered by the low eaves extension, though the top portion of a lancet window is exposed above the extension ridge, now truncated to form a lunette. This extension is domestic in character, with a low eaves line, small rectangular three-light windows in each elevation, and a short square chimney on the gable. Both east and west faces contain pairs of rectangular ledged timber doors set in glazed screens leading into a new north porch. A circular datestone inscribed '1995' appears below the chimney on the north gable. The east elevation mirrors the west in its elements and openings.

The church is approached from the main road by a tarmac path dividing to run around the building's sides and rear. The grounds comprise a grassy graveyard to the front and grassy banks to the rear. A densely packed burial ground occupies rising ground to the east, and a modern tarmac car park sits on higher ground to the north, reached by a driveway and linked to the lower churchyard by a modern stepped path with modern iron railings. The front boundary is formed by a smooth rendered wall topped with rough stone copings, containing a recessed main gateway of original High Victorian ornamented gates and iron piers inscribed 'Musgrave, Belfast', flanked by curved screen walls.