January 1 1979 Lithgow NSW Australia
"The Lithgow Zig Zag was a zig zag railway built near Lithgow on the Great Western Railway of New South Wales in Australia which operated between 1870 and 1910, to overcome an otherwise insurmountable climb up the western side of the Blue Mountains. It is now used by the Zig Zag Railway, a narrow gauge tourist railway." (Wikipedia)

Australia has many similarities to Canada. One of them is that a transcontinental railway has some difficult mountains to traverse.  The Lithgow Zig Zag (switchbacks in North American terms) was equivalent to the Field Big Hill on the Canadian Pacific Railway.  As soon as technology and money permitted, a tunnel replaced the difficult operations of both.
In the picture can be seen both the tourist train which in 1979 used locomotives just out of commuter service in Brisbane and the later electrified line which uses the tunnel to move large amounts of coal.