Due to constraints imposed by geography and lack of government investment, Hurstbridge line is both notable and notorious for having several parts of single rail track along the 15 km section between Greensborough and Hurstbridge. Both Eltham and Diamond Creek stations have two platforms, which provide places at which trains can pass. This section of unduplicated track includes a timber trestle bridge near Eltham station that has heritage protection. The bridge has a 40 km/h speed limit. These single-track sections create bottlenecks at which trains must often wait for up to 10 minutes for an oncoming train before proceeding.