. ▁A ▁ 1 5 4 - met re - long ▁tunnel ▁also ▁exists ▁on ▁the ▁He ales ville ▁line , ▁as ▁well ▁as ▁three ▁t unn els ▁on ▁the ▁sub urban ▁Hur st bridge ▁line , ▁and ▁another ▁on ▁the ▁fre ight ▁lines ▁under ▁Foot sc ray ▁station . ▁ ▁On ▁the ▁inter state ▁railway ▁cor rid ors ▁there ▁are ▁independent ▁sections ▁of ▁track ▁due ▁to ▁the ▁use ▁of ▁both ▁broad ▁and ▁standard ▁gau ges ▁in ▁the ▁state , ▁these ▁sections ▁being ▁from ▁Melbourne ▁to ▁Se ym our ▁and ▁on ▁to ▁Al bury ▁( construct ed ▁in ▁the ▁ 1 9 6 0 s ), ▁and ▁Melbourne ▁to ▁Ge el ong ▁( comple ted ▁in ▁ 1 9 9 5 ). ▁The ▁gauge ▁issue ▁also ▁sees ▁dual ▁gauge ▁track ▁used , ▁in ▁areas ▁including ▁Mary borough , ▁North ▁Ge el ong , ▁and ▁various ▁fre ight ▁terminal s ▁in ▁Melbourne . ▁ ▁The ▁maximum ▁speed ▁of ▁sub urban ▁electric ▁multiple ▁units ▁and ▁locomot ive ▁ha u led ▁trains ▁is ▁ 1 1 5   km / h , ▁with ▁dies el ▁multiple ▁units ▁permitted ▁up ▁to ▁ 1 3 0   km / h ▁on ▁the ▁same ▁track , ▁and ▁up ▁to ▁ 1 6 0   km / h ▁on ▁specified ▁lines . ▁The ▁maximum ▁ax le ▁loading ▁of ▁fre ight ▁w ag ons ▁is ▁ 2 0 ▁t onnes , ▁with ▁locomot ives ▁of ▁up ▁to ▁ 2 2 ▁t onne ▁ax le ▁loading ▁operating . ▁Train ▁lengths ▁are ▁limited