Denmark Norway London Helsinki Manila Sweden Thailand Estonia Scotland Korea Greenland China Rome Warsaw Spain Gibraltar Berlin Madeira   Riverside storehouses. The riverside storehouses surrounded a medieval harbour into which salt and other products were imported. The full export rights of a staple town were first conceded to Porvoo as early as the 16th century. Since the rise of mercantilism in the 17th century, butter, timber, dried fish, linen and tar were items exported from Porvoo although tar had to be sold via Helsinki.