The capital of Finland, Helsinki, is definitely not yet known as one of the best places to see street art in Europe, but there's plenty of potential out there. Helsinki City center is not the place to find graffiti or murals, but if you're curious enough and happy to venture a little further you can find multiple exciting destinations. What's great is that most of these are easily reached with public transport, cycling or by walking around.
Maps of Street Art destinations in and around Helsinki, Finland
Pasila Street Art District, Helsinki by Helsinki Urban Art
Street Art orienteering Helsinki, Vantaa & Espoo by Helsinki Cycling association Helsingin Polkupyöräilijät Ry #katutaidesuunnistus Street Art in Espoo by Urban Espoo
With Street Art everything is always temporary and constantly evolving.