Americans call them 'The Subway', the British call them 'The Underground' or 'The Tube'.
there are no underground power lines but a zone holds it (power) cause the buildings need power so they hold it. and form like a circuit or you call it a underground power line.
In Chicago they are referred to as El Trains (elevated trains).
they call it that because it was underground and its was a rail road
an engineer
Conductors.
Tamer
a pigeon trainer
Steam Trains
Underground railways are known, in the USA, as the subway.
Dungeon
Siderodromophila
Paraphernalia