The railway network is large, comprising a total of 33,819 km (2,540 km electrified) of track: 3,719 km broad gauge, 15,422 km standard gauge, 14,506 km narrow gauge and 172 km dual gauge. Rail transport started in the various colonies at different dates. Privately owned railways started the first lines, and struggled to succeed on a remote, huge, and sparsely populated continent, and government railways dominated. Although the various colonies had been advised by London to choose a common gauge, the colonies ended up with different gauges.