The capital and biggest city in Finland is Helsinki. It is in the south about 2 h by bus or train away from Turku. When you want to go to the capital and you are early enough you might get the Onnibus for 2€ one way, so 4€ in total or a cheaper train with the safer ticket at around 7€ one way. I noticed in the first week of the orientation, that people are not happy about the fact, that Helsinki "stole" the title of Finland's capital in 1812, when the Russian czar Alexander I decided Turku was too far away from Russia and Helsinki was better, because it was so close to Saint Petersburg. After Finland's independence Helsinki stayed the capital and the city grew a lot, when the Russian declared it capital it had 4000 inhabitants, now it has 643272 inhabitants in 2018 . Helsinki is a very nice city at the ocean and with its connections to Saint Petersburg, Tallinn and the biggest airport in Finland "Helsinki-vantaan lentosema" it is a important place for traveler.
I only seen some of the city because I never had enough time to enjoy it properly. I stayed there one night before going to Tallinn and what I saw was nice, which was the day when I got my tattoo here in Finland. When you are interested in getting one I can recommend the Tattooshop https://tatuata.com/ they take walk-ins every Saturday and the Tattooartist who tattooed me, Alex, was very friendly and talented.
Reference:
https://www.hel.fi/hel2/tietokeskus/julkaisut/pdf/18_12_21_tasku18_saksa_net.pdf
