Complex sentence: Canadian artist Fritz Brandtner created the three large chiselled stone reliefs depicting Mercury, Apollo and Poseidon on the station's north exterior wall; these were obscured by the 1958 construction of the neighbouring Queen Elizabeth Hotel.
Split into simpler sentences: Canadian artist Fritz Brandtner created the three large chiselled stone reliefs depicting Mercury, Apollo and Poseidon on the station's north exterior wall. These were obscured by the 1958 construction of the neighbouring Queen Elizabeth Hotel.