▁to ▁ 1 2 0 0 ▁metres , ▁except ▁on ▁the ▁main ▁inter state ▁lines ▁where ▁ 1 5 0 0 ▁met re ▁long ▁trains ▁are ▁permitted . ▁ ▁Track ▁gauge ▁ ▁The ▁majority ▁of ▁the ▁rail ways ▁of ▁Victoria ▁are ▁of ▁ ▁broad ▁gauge , ▁present ing ▁break - of - g au ge ▁difficulties ▁when ▁connections ▁were ▁made ▁with ▁New ▁South ▁Wales ▁which ▁uses ▁the ▁ ▁standard ▁gauge . ▁In ▁addition , ▁the ▁Victor ian ▁Rail ways ▁experiment ed ▁with ▁four ▁short ▁narrow ▁gauge ▁lines ▁of ▁ ▁in ▁the ▁early ▁ 2 0 th ▁century . ▁E ff ort s ▁to ▁eliminate ▁the ▁gauge ▁issue ▁were ▁proposed ▁many ▁times ▁in ▁the ▁interven ing ▁years , ▁with ▁a ▁Royal ▁Commission ▁in ▁ 1 9 2 1 ▁dec iding ▁" that ▁the ▁gauge ▁of ▁ 4 - ft . ▁ 8 . 5 - in . ▁be ▁adopted ▁as ▁the ▁standard ▁for ▁Australia ; ▁that ▁no ▁mechanical , ▁third ▁rail , ▁or ▁other ▁device ▁would ▁meet ▁the ▁situation , ▁and ▁that ▁uniform ity ▁could ▁be ▁secured ▁by ▁one ▁means ▁only , ▁viz ., ▁by ▁conversion ▁of ▁the ▁gau ges ▁other ▁than ▁ 4 - ft . ▁ 8 . 5 - in ." ▁ ▁By ▁the ▁ 1 9 5 0 s , ▁inter state ▁traffic ▁was ▁suffering ▁from ▁the ▁break - of - g au ge ▁at ▁the ▁New ▁South ▁Wales ▁state ▁border , ▁and ▁a ▁parallel ▁standard ▁gauge ▁line ▁was ▁opened ▁from ▁the ▁Melbourne ▁to ▁join ▁the ▁New ▁South ▁Wales ▁system