Head Post Office Building

The Head Post Office Building is an ornate structure featuring three storeys and an attic, with a front elevation that has five bays, faced with red brick and terracotta. The attic storey includes a central window with three lights set in reveals behind short half-columns, topped by a lunette inscribed with "ERII" and further adorned with a gable featuring egg and dart mouldings. The end bays on the second and first floors have a narrow rectangular window set within a pilaster at the second floor level and an oval lunette at the first floor level. The central three bays on both the second and first floors are recessed behind an Ionic portico in antis; the second floor has three semi-circular windows, while the first floor features three rectangular transom and mullion windows with a moulded architrave and keystone. An entablature runs along the first floor level.

On the ground floor, there is a pilastered round-headed doorway in the centre with coved jambs and an ornate keystone, flanked on each side by a three-light window. To the right in the end bay, there is a round-headed window, and to the left, there is another doorway.

The Post Office now incorporates the left part of the original Mostyn Art Gallery Building, which consists of two bays, three storeys, and an attic. The attic features a three-light window with a segmental pediment above the centre. The second floor has two lunette windows, while the first floor includes two canted bay windows. On the ground floor, there is a round-headed doorway to the left and two windows. A cast iron verandah spans three bays.