Thank you very much, Marjatta from Turku (Finland) for this really magnificent cover!I received this cover through the postcrossing circuit. I signed up last week, and this is the first cover I received. And I'm very happy with it as you can see :)
On the cover you see a drawing of the castle of Turku, where the city's historical museum is housed (since 1881!). Turku was the first capital city of Finland. (http://en.wikipedia.org/wiki/Turku)
Marjatta writes that the stamp is unique for the medieval market. I could not find a stamp like this one on the internet. I thought that maybe this is a personalized stamp from Finland?? Does anybody know? Please let me know if you do!