Hello,
Uusikaupunki is unique city. One of the reasons is the car factory. The second is the museum of old cars.
See link: https://visituusikaupunki.fi/en/what-see-and-do/automobile-museum
Not only in the museum you can see old cars. There are on the Uusikaupunki's streets also. It was the first time for me when I saw such old cars on the streets. They look very originally on the background of wooden buildings.
I feel that oldtimers are popular not only in Uusikaupunki but also in the whole of Finland.