St Mark’s is constructed, as are many of Aberdeen’s fine buildings, of local granite. The front elevation is a close ashlar on a rock-faced base, with the remaining walls hammer dressed Kemnay granite.   A classical design by A Marshall Mackenzie the building features a giant portico surmounted by a drum and high dome modelled on St Paul’s Cathedral. The church, along with its neighbours, His Majesty’s Theatre and the Central Library, “forms the most distinguished grouping of major buildings in Aberdeen” (Historic Buildings Council for Scotland, October 2000).