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.

An additional 2 stations and 55 kilometres (34 mi) of railway are traversed by Southern Highlands trains at peak hours.

The Main South line opened in stages to Picton in 1863, Moss Vale in 1867 and Goulburn in 1869.

Most services operate between Campbelltown and Moss Vale with a limited number extending to Sydney Central and Goulburn.

[3] Some stations are also served by NSW TrainLink XPT and Xplorer services from Sydney to Canberra, Griffith and Melbourne.