The former Oamaru Railway Station, designed by Railways Department architect George Troup, and opened in October 1900, has architectural and historical significance as a typical station built in major provincial centres around the turn of the twentieth century.

In 1873, the first Oamaru Railway Station was built at the foot of Wansbeck Street, serving as a public works office until the lines began to operate. The first lines to operate were the breakwater line at the harbour, and the section between Oamaru and the Waitaki River, which opened on 27 September 1875. The line up the Waitaki Valley also opened in 1875, the line to Christchurch in February 1877, but it was not until 1878 that the line to Dunedin opened. Trains into Oamaru from the north had a straight run in, but trains from the south had to be reversed from the crossing at Thames Street. In the late 1870s, the town discussed the need for a new station, leading to debates about the best location, but for the time being, the existing station was only enlarged.

There were prolonged discussions about relocating the station to do away with the need to reverse into Oamaru. It was not until 29 October 1900 that the new station on Humber Street was used for the first time. The Humber Street location changed the ‘centre of gravity of the town’, moving business toward the north. The previously bustling Tyne Street area lost much of its energy.

Rail heritage enthusiasts call this station ‘Vintage Troup’, meaning it was built in the first decade of the twentieth century to the design of railway architect George Troup. Oamaru Railway Station has Troup’s trademark style, with its ‘elaborate porte-cochere’ hinting at Troup’s style that would find its full flowering in his 1906 Dunedin Railway Station. The Rail Heritage Trust of New Zealand provides a description of the building which is paraphrased here. It is a long slender building, basically rectangular in plan. The entrance to the street is defined by a gabled porch, with width of a porte cochere [an entrance wide enough for a vehicle], flanked by a verandah with turned timber posts. The gables on the road elevation have decorative infill. There are brick chimneys at intervals along the roof. The platform elevation has a long gabled verandah, supported by rails. The interior has been modified.

In 1908 a ladies' waiting room was added to the building and the same year a footbridge was approved. This footbridge was replaced in 1924 and demolished in 1958. There were few additions to the station building, but many alterations. In particular the 1950s saw many changes to the building interior in an effort to accommodate the expanding staff and functions. Until the mid-1980s Oamaru was an important division point for train crews, but changes in operating methods and a reduction in local traffic led to the withdrawal of station staff in 1990.

Oamaru Railway Station was famous for its large dining room, the largest in the South Island till its closure in 1967. The Christchurch–Dunedin express made a regular 22-minute dinner (lunch) stop here, and for a set price of 2s 6d, travellers could sample delights such as ‘stewed tripe and oysters’, ‘smoked fish with butter sauce’, ‘roast sirloin of beef with Yorkshire pudding’ and ‘compote of pears with boiled custard’. Passenger trains stopped calling at the station in 2002. In 2015, the former Oamaru Railway Station stands as a reminder of Oamaru’s importance on the main trunk line.