Helsinki-Vanda Airport is 19 km from the centre. The bus to Tölögatan and the railway station takes 30 minutes and costs approx 5.20 Euro. Taxi approx 25 Euro.
The boats stop almost in the centre of the city. Bus/tram from the terminals to central Helsinki, unless you’d rather walk.
Helsinki has ferry connections to Sweden and the Baltic States.
There are boat connections to many sights including the Fortress of Suomenlinna. Touring and sightseeing boats depart from Salutorget.
It is easy to get around anywhere in Helsinki by public transport. There are trams, buses and tubes (called Metro). Buy a tourist ticket for one or more days or, easier and more flexible still: get a Helsinki Card for all your journeys within Helsinki and lots of other benefits.