Blue Mountains Line

The Blue Mountains line is a section of the Main Western line which opened in 1868. The line was built with gradients as steep as 1 in 33 (3%) and curves as sharp as 8 chains (160 m; 530 ft). Most of the curves were eased to 12 chains (240 m; 790 ft) with duplication.

The line originally ascended the eastern and descended the western sides of the Blue Mountains via a series of zig-zag track sections. The eastern zig zag was by passed by a tunnel in 1892 and the western zig zag (currently a tourist railway) was bypassed in 1910 with the Ten Tunnels Deviation.

Electrification and further upgrades

In the 1950s, the line was electrified primarily as a means of easing the haulage of coal freight from the western coalfields to the coastal ports, but a by-product of this programme was the introduction of electric interurban passenger services as far west as Bowenfels, later cut back to Lithgow. Goods trains are now exclusively diesel hauled. Electric passenger services were originally provided by a combination of electric locomotive hauled carriages and single deck electric multiple unit sets (known as U sets), both of which have now been withdrawn and replaced by more modern rolling stock.

In June 2012, New South Wales Premier Barry O'Farrell announced that services would be extended to Bathurst. The service, commonly known as the Bathurst Bullet, commenced on 21 October 2012. A second Bathurst Bullet return service was introduced on 16 September 2019. Springwood services were previously the only services where an H set train would be scheduled. Due to the width of H sets, they risked striking platforms past Springwood with their outward opening plug doors and tunnels past Katoomba. The last H sets were removed from the line in 2017 and 2018, but they are still used as a replacement train.

Due to the increased width of the New South Wales D set compared with its predecessor, the V sets the loading gauge of the line past Springwood was increased. This was done by a combination of carving notches into tunnel walls and reducing required clearances by lowering speed limits. The New South Wales D set or Mariyung trains entered service on the line on 13 October 2025.

Station upgrades as part of the Transport Access Program (TAP) were carried out, as well as more minor upgrades. A full list of completed upgrades can be viewed at the TAP's completed projects page, whilst current projects can be viewed here.

All electric Blue Mountains line services start and terminate from the intercity platforms (4-14) of Central (Sydney Terminal) station. During the weekday off-peak, they operate hourly, alternating between services to Mount Victoria and Lithgow. During the morning and afternoon peaks, some express services operate, together with short workings to Springwood and Katoomba.

There are two daily services each way between Bathurst to Central, known as the Bathurst Bullet, mainly catering for commuters working in Sydney. Two services run toward Central in the morning and return in the afternoon. Two shuttle services operate from Lithgow to Bathurst in the early morning and return to Lithgow late at night. Some off-peak electric interurban services on the line only consist of four carriages, with peak hour services usually consisting of eight carriages. Regional diesel services on the line consist of two carriages.

• New South Wales Endeavour Railcar N set 2 car DMUs, (Central-Bathurst services)
• New South Wales D set 4, 6, 8 or 10-car EMUs, (Central to Springwood, Katoomba, Mount Victoria or Lithgow)

The following table shows the patronage of each line of the NSW TrainLink Intercity network for the year ending 30 June 2026, based on Opal tap on and tap off data.