One of only two routes on the NSW TrainLink intercity network to run entirely on non-electrified railway lines, the Southern Highlands Line is operated with a rolling stock solely consisting of Endeavour railcars, with most services only using two cars. The service spans 169 kilometres (105 mi) of railway, making it the most extensive route on the NSW TrainLink network apart from the Blue Mountains Line's Bathurst Bullet service. Despite that, the route spans only 22 stations, making it also the route with the lowest number of stops. An additional 2 stations and 55 kilometres (34 mi) of railway are traversed by Southern Highlands trains at peak hours.
In 1919, a new section of line opened between Picton and Mittagong, with the original section becoming the Picton-Mittagong loop line.[2] Originally a single track line, it was later doubled with the exception of the Picton-Mittagong loop line.
Rail replacement bus services operate between Picton and Bowral paralleling the Picton-Mittagong loop line and Bundanoon and Wollongong paralleling the Moss Vale-Unanderra line. A daytime bus service also operates between Moss Vale and Goulburn.[3] Some stations are also served by NSW TrainLink XPT and Xplorer services from Sydney to Canberra, Griffith and Melbourne.[4]
Up until the mid-1990s, most services on the line operated through to Sydney Central. Named trains that operated on the line included the Goulburn Day Train and Southern Highlands Express. In the late 1980s, air-conditioned HUB/RUB carriages were introduced. These would later be joined by Budd and Tulloch carriages and DEB railcars.[5]
In 1994, all were replaced by Endeavour railcars.[6] Most services were altered to operate only as far north as Campbelltown connecting with Sydney Trains electric services to Sydney.
As of 2014–15, the Southern Highlands Line experiences significantly worse peak hour on-time running performance than other suburban and intercity lines.[7]
The following table shows the patronage of each line of the NSW TrainLink Intercity network for the year ending 30 June 2024, based on Opal tap on and tap off data.[8]
