Dandenong railway line triplication
The Dandenong railway line triplication project was an initiative of the Government of Victoria, Australia, to add sections of third track from Caulfield to Dandenong on the Gippsland railway line to increase capacity of and relieve congestion. The project underwent a reduction in its scope after being first announced in 2006.
Source: Wikipedia — Dandenong railway line triplication (CC BY-SA 4.0)