St John's Episcopal Cathedral, George Street, Oban

St John's Episcopal Cathedral on George Street, Oban, is a church built in three distinct phases during the 19th and early 20th centuries: 1864, 1882, and 1910.

The existing church now comprises two aisles arranged in five bays running north to south, forming an approximate cruciform plan with a sacristy at the north end. The original church and the second-phase aisle, both oriented east to west, are located at the south end of the later 1910 building. The main entrance is at street level from George Street, while the site slopes downward to a basement floor level at the rear (west) of the building. The grey stonework of the earlier phases has been painted to match the red squared and snecked sandstone of the third phase.

The first building phase (1864) was designed by J Thomson of Glasgow and consists of a simple rectangular parish church in plain gothic style. Its east window features three lights with geometric tracery supporting roundels filled with stained glass, which were retained when the building was reconstructed in 1910 as a gable breaking the eaves. The gable contains two stained glass lancets and a rose window with stained glass in its outer lights, with an angle buttress at the corner. The original pitched grey slate roof has been partially altered—the north pitch and corresponding structural timber were removed and replaced with a flat roof connection to the 1910 building, so this section now functions as the rear of the nave to the later church. A south-facing porch at the east end was obscured by a later porch leading into the 1882 side aisle. A corresponding porch from the 1864 phase remains at the west end of the north wall, buttressed, with an iron cross finial and ornately hinged timber two-leaf doors.

The second building phase (1882) added a side aisle to the south, also in simple rectangular plan and plain gothic style. An entrance porch with buttress and pointed arch doorway is attached to the east gable wall, which features a hoodmoulded rose window and iron cross finial above. The south wall extends five bays, each with a single lancet window, and angle buttresses are positioned at the corners. The simple pitched grey slate roof terminates with a plain console at the end of the skew cope. This section now functions as a narthex and baptistery, divided from the nave by a glazed screen with doors designed by Ian G. Lindsay & Partners in 1958.

The third building phase (1910) was designed by James Chalmers of Glasgow and represents a proposed cruciform plan in plain Romanesque style. The design included a west transept and west side aisle, though the west side of the nave remains unbuilt. Round-arched windows characterise this phase, including a triple window in the east wall of the transept with a vesica above. The grey slate pitched roof features a rooflight over the crossing in place of the proposed tower, with a cornice of square moulding and masks at the eaves. Buttresses and angle buttresses reinforce the structure. One bay of the nave arcade was constructed, with circular columns supporting round arches and stained glass windows above. A window on the east side has been infilled behind glass. A shallow west aisle contains stairs to the pulpit, which is Romanesque in style—circular with three main arches containing two subordinate arches, constructed from red sandstone and decorated with onyx, alabaster, and marble. The crossing arches to east and west survive in place, while the arches to north and south remain unbuilt; columns for these arches support recent structural steelwork. The west archway has been infilled with masonry, serving as a backdrop to an eagle sculpture and bishop's stall.

Choir stalls and two lecterns occupy a raised granolithic floor accessed from the nave by three white and green marble steps. Low walls to either side are constructed from pink sandstone with yellow marble copes. An organ by Blackett & Howden of Glasgow is positioned within the east crossing arch, supported on three arches carried on octagonal columns, with springers for corresponding arches in the west crossing. Decorative relief panels adorn the organ case. The chancel is accessed by a green and white marble step to a granolithic floor, beyond which six further green and white marble steps rise to the high altar. A timber reredos above a sandstone frame, decorated with carved cherub heads and lugs, is inset with coloured marble panels. Octagonal pedestals above support sandstone sculptures. A piscina and sedilia of three seats in a single round-arched recess occupy the east wall of the chancel. A Romanesque arch of single order, set with the Bishop's crest, is positioned in the west wall of the chancel.

The Lady Chapel (east transept) has its north wall supported on a round arch, which in turn rests on half-round columns set on rectangular corbels. Beyond the north wall is a rectangular recess serving as a reredos to a yellow marble altar. A Romanesque-style arched doorway opens to the left of the altar. A low brass screen decorated with grapes is surmounted by a timber handrail. The ceilings of the Lady Chapel, nave, and chancel are lined with timber strips forming barrel vaults. The internal stonework consists of stugged, squared, and snecked pink sandstone, with droved ashlar used for columns and decorative details. The basement at the George Street front is lit by a narrow area protected by wrought-iron railings.