Thomas Bonnar, 1824-25. 3-storey, basement and attic, 64-bay classical palace block forming crescent. Droved sandstone ashlar at basement, polished V-jointed sandstone ashlar rustication at principal floor (painted at SW terminal pavilion), polished sandstone ashlar with polished dressings at 1st and 2nd floors. Base course to principal floor; band course between principal and 1st floors; iron trellis balconies to 1st floor; cill course to 2nd floor windows, band course incorporating string course above 2nd floor windows; cornice and coped blocking course to 3rd floor; stone balustrade at roof of central 9-bay pavilion. Ionic porticos to ground, with pilasters behind supporting columns; giant Ionic pilasters to 1st and 2nd floors, central and terminal pavilions; architraves to 1st floor windows of remaining bays, corniced to 3 central bays; dormer windows breaking mansard roof; entrance platts oversailing basement, with ashlar steps at SW end.
NW (PRINCIPAL) ELEVATION: 59-bay concave central block flanked by 2-bay terminal pavilion to NE and 3-bay terminal pavilion to SW.
NE terminal pavilion: windows to both bays, all floors; giant rusticated pilaster at 1st and 2nd floors to outer left; pilasters flank 1st and 2nd floor windows of bay to right. Main (curved) block: portico to penultimate bay to left at ground floor, and to doorways of 9-bay central pavilion; recessed timber doors with plate glass fanlights; giant Ionic pilasters to 1st and 2nd floors to 4 outer bays at each end and central pavilion; continuous balconies at 1st floor to pilastered bays, balconies in 3-bay sections to remaining bays; individual iron balustrades to 2nd floor windows of 6 bays at left of central pavilion; regular fenestration. SW terminal pavilion: portico to bay to left at ground floor; regular fenestration to bays to right and to upper floors; corniced panel at wallhead to outer right.
NE (CANNING STREET) ELEVATION: asymmetrical; single window to centre to ground floor, bipartite windows to centre of 1st and 2nd floors flanked to left by single window, pair of windows to upper floor; variety of infilled openings. Blind pointed-arched openings to 1st floor of left return. 20th century addition to outer left.
SE (ATHOLL CRESCENT LANE) ELEVATION: predominantly regular fenestration; variety of additions and alterations, some linking mews blocks (see below).
SW (ATHOLL CRESCENT LANE) ELEVATION: window to centre of ground floor, band of 4 modern window openings to right. Single window to centre of 1st floor, flanked by small openings to right; window to centre of upper floor flanked to left and right by small openings. Single storey harled addition to outer right.
2, 12, 15 and 16-pane timber sash and case windows. Grey slate mansard roof with variety of dormers, principally modern box. Coped skew at NE end. Coped and rendered stacks with moulded cylindrical cans. Cast-iron rainwater goods.
INTERIORS: not seen 2000.
RAILINGS AND LAMP STANDARDS: iron railings, majority fleur-de-lys design, to street and entrance platts; original railing-mounted iron lamp standards with glass globes and drum wells to street at NE end.
9, 10, 13, 15, 18 AND 20 ATHOLL CRESCENT LANE: predominantly 2-storey mews buildings, rubble and ashlar. 20 Atholl Cresent Lane: 2-storey, 3-bay. Sandstone ashlar to N. Eaves blocking course.