National Museum of Wales

The National Museum of Wales is a substantial building dating from the early 20th century, constructed in a classical style that combines elements of Grecian Doric architecture with a simplified version of the Baroque style seen in nearby City Hall and Law Courts. The exterior is faced in Portland stone, topped by a lead dome. The building generally rises one massive storey above a basement, with small-pane metal windows.

The finely proportioned south-eastern front is accessed by a double flight of granite steps leading to a recessed portico. This portico features coupled Doric columns, a balustraded parapet, and a granite architrave framing the doorway, which has bronze doors. Above the portico is a recessed attic storey. The centre of the entrance hall is dominated by a semi-circular dome, 30 metres high, supported on an octagonal drum with concave corners decorated with heraldic beasts carved into their facets, and lunettes above the windows.

Flanking the central portico are wings of three bays, featuring horizontal rustication and tall rectangular windows. The centre bay of each wing projects forward, with a window flanked by Doric columns in antis, surmounted by an entablature, and an attic adorned with groups of sculpture. A long west wing extends in the same style, with two advanced blocks featuring four Doric columns flanked by piers, enclosing three tall windows. The east wing culminates in a central semi-circular lecture theatre with thirteen windows, flanked by doorways with fluted Doric columns. The returns of both east and west wings are characterised by tall, round-headed windows. Modern courtyard galleries were added in 1993, situated between the original wings.

The magnificent and spacious entrance hall boasts polished marble columns and flooring. The central octagonal space beneath the central dome features thermal windows glazed with original pink glass. Tall piers are folded around the inner angles of the octagon. Lower sections of the hall are characterised by coffered ceilings and a gallery running around the entire hall at a high level, supported by Ionic columns. Broad staircases ascend at each end, passing below gallery bridges and dividing to provide access to the gallery and stairs. These upper staircases are lit by glazed saucer domes. At the upper level of the octagon, further stairs lead to a balcony giving access to a Library and Courtroom, both panelled with Doric pilasters and thermal windows, as well as other offices. Display galleries, including the Joseph Gallery and Pyke Thompson Gallery, are situated at the front of the building and are in a classical style, incorporating saucer domes. The semi-circular lecture theatre is reportedly inspired by Ledoux's Besancon Theatre from the 1770s and includes a clerestory of windows behind unfluted Doric columns, and a semi-circular gallery above the theatre. Additional galleries are located within the rear wings, displaying various styles. Modern, spacious, and light courtyard galleries were added in 1993.