The Shellharbour district was initially reliant on coastal shipping for its connection to Wollongong and Sydney, but this changed with the construction of the South Coast railway line to Wollongong in 1887, and its connection to Sydney the following year. Dunmore Station opened along with the Wollongong–North Kiama extension in 1887, with a single platform, weatherboard platform building and Victorian–Georgian brick stationmaster's residence. The station was used by passengers from nearby Shellharbour; the main freight users were local pastoralists and the neighbouring basalt quarry. The growth in quarry traffic necessitated the construction of a goods siding in 1923 and a signal box two years later. The station was refurbished around the same time. In 1940, a second side platform ("platform 1") was added. The flow of rail freight from the district waned in the late 20th century, however, and the goods siding was removed in 1970. The old station buildings, still extant today, are located near where Dunmore Road (formerly Shellharbour Road) intersects with the railway line, at the southern end of Dunmore.