Sweden

Sweden is a country on the Scandinavian Peninsula in Northern Europe. It is bordered by Norway to the west and Finland to the northeast. Its capital city is Stockholm.

History
In the summer of 1995 one of Cho Chang's friends were in Sweden.

Xenophilius and Luna Lovegood believe that Crumple-Horned Snorkacks are native to Sweden and went on an expedition to find them there in the summer of 1996, using the money the Daily Prophet paid them in order to re-print Harry Potter's account of Lord Voldemort's return.

Sweden hosts the annual broom race which dates from the tenth century. The competitors fly from Kopparberg to Arjeplog. The winner receives a trophy shaped like a Swedish Short-Snout.

It is possible that the wizarding school Durmstrang is located in Sweden, although it could also be in Norway. ((Edit: Durmstrang is most likely not in either of those two contries, as the names are not scandinavian whatsoever. Believe me, I live there u__u ))

Notes and references
Suède