The usual name is a subway.
Subways
it means a secret passage
Americans call them 'The Subway', the British call them 'The Underground' or 'The Tube'.
Guildford hasn't got an Underground system, so no underground trains.
An underground series of tunnels with trains running through them. They are used as a form of mass transit allowing pedestrians to get across big cities generally quicker than by car.
All trains are noisy. Underground trains sound noisier because the tunnel reflects the noise back.
Yes, tourists and residents can film trains in the London Underground.
No, Trains and Pedestrians also use it.
No. Luxor, Egypt has only above-ground trains.
Depends what you mean: Firstly, what are 'normal' trains and why are underground trains not 'normal'? Can non-LU trains run on the tube network? A: No, they will not fit in the tunnels Does LU have an intergrated transport network with non-LU trains? Yes, sometimes on adjacent platforms
the answer is metro
Electric traction motors in each car via a "3rd rail" feeding electricity.