What kind subway without railway for the train? that make no sense, right?
We definitely need a train on the subway to make a long journey, safety journey
is someone working on the train? it will be very interesting to transportation cargo between different parts of the new england
Actually I think it would be f`ing amazeing when Z levels are in to have underground subways.
Think about it you go down into the subway and there is a network of platforms etc and monsters every where.
U manage to get the train working and on the track down in the tunnel is a shit load of zeds you plow them down would be fun even more so if the trains used the vehicle construction meru that allows you to mod the train or make more 
In order for this to work effectively there’d have to be some kind of system to manage vehicles on rails. This’d also make an awesome feature for making minecarts, or automated lifts that you can call to transport you or your materials somewhere. You could create your own subway system if you had the resources. Not to mention lifts…
railtracks are alslo good soure of metal
So, how most older rails and subways work is with an immense amount of power, and one of the rails is powered. Hence why touching both kills people because you complete the circuit.
Technically since this more futuristic, they could be more modern rails. Just tracks and the actual engine supplies the power. (Solar isn’t going to work underground).
So if it was the first version, there’s no working power grid in cata. The infrastructure seems to have been destroyed or it’s no longer kept up, because all of the workers that did work in the various power plants, are dead.
I don’t see why there couldn’t be some rails, and like a few subway cars, and a few hundred zombies from those that were on the train when it last stopped though.
Its not old vs new models of trains. Its diesel (usually diesel-electric) powered vs electric powered trains.
Afaik in the US both versions are used.
There could be a railway storage building with spare parts, even whole engines.
So even with no power grid, one could use a diesel train engine to move a train.
Probems: Use of a train might be limited. (Minecarts and tracks may be useful though, for things like chopping down a forest, then transporting the wood)
Iirc there was a PR adding tracks and stations, but it got indefinitely stuck on mapgen.