Skateparks on the map: over 500 skateparks and BMX tracks in Finland, browsable by municipality. Free, no sign-up, no account and no paywall.
504 places in
Most skateparks are in Helsinki (34), Espoo (18) and Jyväskylä (15). The full list is below by municipality, and the map can be filtered to your own area.
The remaining places are on the map and in the municipality list.