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If I'm not mistaken, London also has two different types of tube trains, although in that case I don't think it'd because of different owners, but one is simply
by mcv 3y ago
If I'm not mistaken, London also has two different types of tube trains, although in that case I don't think it'd because of different owners, but one is simply narrower and therefore cheaper to make tunnels for.
- FearNotDaniel 3y agoActually it's both of those, and more complex: multiple private companies building at different times in history, using widely diverse tunnelling techniques and depths to suit different needs. https://en.m.wikipedia.org/wiki/History_of_the_London_Underground https://en.m.wikipedia.org/wiki/History_of_the_London_Underg...
- ianburrell 3y agoThe London sub-surface and deep-level tubes were made by different technologies. Surface by cut-and-cover and deep-level by tunnelling shield. Both were the first of their kind, and deep-level wasn't possible until electric propulsion was invented. The deep-level tunnels are narrow because of the expense of digging by hand.