The first terminus had a single platform 30 metres long, and was located beside the Fish Market building on the south-west corner of Swanston and Flinders Streets. An additional platform was provided in 1877, along with two overhead bridges to provide passenger access, followed by additional timber and corrugated iron buildings and a telegraph station in 1879. The first signal boxes were opened at the station in 1883, one at each end of the platforms. By the 1890s, a third island platform had been constructed. 's two other early central-city stations, Spencer Street and Princes Bridge, opened in 1859. Spencer Street served the lines to the west of the city, and was isolated from the eastern side of the network until a ground level railway was built connecting it to Flinders Street in 1879, this track being replaced by the Flinders Street Viaduct in 1889.