The last train exiting a city and bound for the lower socio-economic suburbs, especially after Friday & Saturday nights.
Although comprising of some decent folk who've had a shandy or two, this train service ferries large numbers of drunk juvenile and young adult non-paying patrons back home from the previous evening's shady dealings, train station fight-clubs & various local pillages.
Catch an earlier train if you can.

When you eat dirt for the first time and leave your family to build a shack in the woods