Zig Zag Railway, bottom points the yards and storage sheds for the steam engines of the zig zag railway.
The Zig Zag Railway is a heritage railway at Lithgow in New South Wales, Australia on the site of the famous Great or Lithgow Zig Zag which operated between 1870 and 1910. As built, the line formed part of the main line railway westward from Sydney across the Blue Mountains and served to lower the line from its summit into the Lithgow valley on the western flank of the mountains.
The original plan, by the newly-appointed Engineer-in-Charge, John Whitton, had been to build a 3km tunnel, but this was beyond the resources of the state of New South Wales at the time. The zig zag alternative still required several short tunnels and some viaducts.
On the eastern side of the range, the first Blue Mountains Zig Zag (known as the Lapstone Zig Zag) opened near Glenbrook in 1867. It ascended Lapstone Hill on a gradient of 1:30 to 1:33 (~ 3 - 3.3%), which contoured up the side of the range with comparatively light earthwork.