In order to speak about city transport, you need the appropriate vocabulary.
Underground - a railway system in which electric trains travel through tunnels below ground;

Danger sign - a notice giving information, directions, a warning, etc;

Signs giving instructions - notices that give information about how to do or perform this or that thing/action;
Trolleybus - a public transport vehicle with rubber tyres that travels along ordinary roads in towns and is driven by electricity supplied from a wire above the road;

Tram - an electric vehicle that transports people, usually in cities, and goes along metal tracks in the road;

Bus - a large vehicle in which people are driven from one place to another;

Taxi - a car with a driver who you pay to take you somewhere;

Double-decker - a bus with two levels;

Bicycle/bike - a two-wheeled vehicle that you sit on and move by turning the two pedals (= flat parts you press with your feet);

Motorized bicycle - a bike specially fitted with an engine or motor;

Motorbike - motorcycle. 

The trolleybus does not run on tracks.

You should take the bus/go by bus (= travel by bus) if you want to see the sights.

I took a taxi from the station to the hotel.

He got on his bicycle and rode off.

Her brother borrowed her motorbike and crashed it.