There is a famous children book in the world that is The Moomins. Many Japanese read its book when they are a kid. If you ask to Japanese what is about Finland, maybe they will answer “The country Moomin born” .
There are many stores and museums about it. If you love Moomin, you should go to Moomin World which located in Naantali. However I would like you to recommend Tampere. There is the Moominvalley of the Tampere Art Museum which very small one but, you can see original picture corrections there.
The city of Tampere is not so big. It would be good to rent bicycle and you can look around all city in 1 day. There are nice brick factory building, river, hill, and nature. Pyynikki observation tower is one of great spot to stop by for tourists. Moreover, local couple and elderly relaxing place as well. 1st floor of this tower, there is a cafe. Then you can have very delicious doughnuts!
The cafe has a terrace table. When you have a doughnut in outside, I am sure you feel so good! In the park, there are nice hiking tracks and stop you can play some sports by the waterside.
The city of Helsinki, there is a place call Fortress of Suomenlinna. This place is World Heritage, and in the web said:
” Built in the second half of the 18th century by Sweden on a group of islands located at the entrance of Helsinki’s harbour, this fortress is an especially interesting example of European military architecture of the time.”
I was interested this place when I went because, there are still local people lives in the island. So you can see local life and stores next to World Heritage.
Of course! there are museums, such as Suomenlinna, Museum,Submarine Vesikko, and so on. It might be good to spend half day in the island to look around.