Portmeirion was designed and laid out by the celebrated architect Sir Clough Williams-Ellis (1883-1978) following his purchase of the estate, then called Aber Ia, in 1926. The village evolved over several decades and was still being added to in the 1970s.

The Pantheon, or Dome, was built 1960-61 to remedy what Williams-Ellis described as the village's `dome deficiency.' The foundation stone was laid by Earl Russell, OM. The Gothic porch originated as a red sandstone fireplace from Dawpool, Cheshire, and was designed by Norman Shaw. The pantheon is a large octagonal building with plastered walls and pilasters at the angles surmounted by a ribbed dome with elegant octagonal cupola and gilded ball finial. Tall arched windows with multi-pane glazing flank a large Gothic-style porch on the south-western side; a sequence of oval oculi runs around the top. The porch is of 2-storeys and originated as a fireplace; painted red sandstone. It has 2 segmentally-headed arches on the ground floor, and 6 narrow windows above, all set in ornamental Gothic decoration, and painted white; parapetted top with eagle sculptures to the canted corners.

Adjoining the Pantheon to the rear is a single-storey addition with rendered elevations and slate roof. This is in the form of two conjoined blocks with an angled central chimney in between; the latter has a cupola-like top with upturned copper wash boiler as finial. Tripartite multi-pane windows, and a part-glazed door to the gable of the western-most section. A short link wall with open arch links the building at this point to the adjacent Chantry Row. Similarly an arch links the eastern block to the corner of the Belvedere.

In front of the Pantheon is a balustraded terrace from which steps lead down to the lane opposite Battery Square.

Source: Cadw listed building description.
RCAHMW, November 2007.