I have done that a few times when fishing!
Logistics and Transport
Whilst not strictly on-topic, but in the same vein, we have 100s of miles of railways in this country. Some are still in use, (Great Western Railways not so much )obviously, but a lot are now disused. They have one point in common with the waterways, though - they are all built on flat terrain so will make easy progress when in a "get home" scenario.
Just because I'm paranoid, doesn't mean they're not all out to get me
Walking on ballast is not as easy as you think. It is tiring and walking just a mile can be challenging. Sleepers and rail are slippery and dangerous to walk on, third rail is deadly at 750v dc. Though i will use the railways to return home if i'm in work when SHTF as i drive trains for a living.