St John's Church, Walls, Hoy

St John's Church, built in 1881, is a rectangular Church of Scotland church that originally served as a mission church. It has a symmetrical design with five bays. A small, gabled, rectangular porch is centrally positioned on the west elevation, and an almost identical vestry is centrally placed on the east. The exterior is harled with ashlar dressings, with those below roof level painted cream. It features architraved openings throughout and vertical margins at the arrises. There are coped gables and a small bellcote at the east end.

The north elevation displays regularly spaced windows, one in each of the five bays of the nave. The entrance porch is set back to the outer right, containing a four-panel timber door and a window to the right of the door. The vestry is set back to the outer left and features a central window. The south elevation is similar, with regularly disposed windows and the vestry set back to the outer right, featuring a low pointed arched lintel over a boarded timber door and a window to the right. The entrance porch is set back to the outer left on this side.

The west elevation has a projecting gable end for the entrance porch, with a central window and a fleur-de-lys finial to the gable. Flanking, recessed windows are set back from the gable end of the nave, with one above, set into a slightly projecting vertical band. The square-plan bellcote has a gableted lancet opening on each side and is surmounted by a small pyramidal spire with a truncated finial.

The east elevation displays a blank gable end for the vestry and flanking, recessed windows set back from the gable end of the nave, with one window above. A truncated finial sits atop the gable.

The windows are timber, with three panes to each frame. The main building and vestry have a Welsh slate roof, while the porch has an asbestos slate roof.

Inside, the nave opens to a king post roof. The floor is timber with a stone-flagged central aisle. The church features plain-boarded timber pews. A hexagonal timber pulpit has simple Gothic panels to the upper section and back and steps with a cast-iron handrail. A modern sounding board is also present. Original gas lamps are mounted on wrought-iron brackets and suspended from the ceiling alongside modern electric lighting. Four-panel timber doors are used throughout. The entrance porch is matchboarded, and a brass tablet commemorates four men 'of this church' who died in World War I.

A coursed rubble boundary wall encloses the rectangular churchyard. Two adjoining entrance gateways—one for pedestrians, one for vehicular access—are located on the north side, featuring square-plan gatepiers with timber gates. The gates have latticed upper panels and railed lower ones.