The east and west interior walls of the station feature two large bas-reliefs depicting Canadian life, arts and industry, designed by Charles Comfort and executed by Sebastiano Aiello. Included in the bas relief are a few of the lyrics of O Canada, which still was not the national anthem when the station was built. The lyrics are in French on the east side of the station and in English on the west side. Canadian artist Fritz Brandtner created the three large chiselled stone reliefs depicting Mercury, Apollo and Poseidon on the station's north exterior wall. The representations of Mercury and Poseidon measure approximately 2,5m by 4,5m. Apollo is larger but visual access is very limited. These were obscured by the 1958 construction of the neighbouring Queen Elizabeth Hotel. It is disputed whether Comfort or Brandtner created the thematic stone medallions depicting water, land and air transportation on the station's west, south and east exterior walls. Stylistically, however, the bas-relief medallions bear a strong resemblance to the frieze by Charles Comfort created for the Toronto Stock Exchange building in 1937.