At this 15th-century stone-and-wood cathedral, the diet of the first duchy of Finland was held in the 1800s, making Finland semiautonomous for the first time. This is one of the oldest churches of its kind in Finland—it's survived being burned to the ground by both Danish and Russian armies on several occasions. Inside, you can make out some of the original Catholic artwork, before the Protestant Reformation meant the whitewashing of its walls. Just outside the front
gate are some of the best views of the surrounding town.