The station was built using cut and cover construction. In December 1973 to permit excavation of the station, La Trobe Street and its tram tracks were temporarily relocated to the south onto the site of what is now the Melbourne Central Shopping Centre, and moved back on completion of the work in 1978. The pit was long and wide, deep at the Swanston Street end and deep at the Elizabeth Street end. Seven layers of struts were used to support the excavation, with 2,600 tonnes of steel temporary supports required.