Helsinki has a very efficient public transport system. It consist of trams, trains, buses, ferries and the metro (underground subway system).
Access to Helsinki’s metro and trams is trust-based – it is up to you to pay for your ticket before you use them. Random inspections are done and if you are found without the correct ticket you may face a large fine.
Currently, children under the age of 7 travel for free. So do adults who are travelling with a child in a stroller.
For more information on tickets, prices, timetables and rules visit http://www.hsl.fi