Visit BAY of KOTOR in Montenegro
If you want to spend a nice day at sea, in the most southern fjord in Europe, you should definitely visit the Bay of Kotor. In fact, the so called fjord is a submerged river canyon of the disintegrated Bokelj River which used to run from the high mountain plateaus of Mount Orjen. The bay has been inhabited since antiquity and has some well preserved medieval towns.
By boat you could take a panoramic ride through the Bay of Kotor enjoying the sight of steep mountains and calm sea. Don't miss to stop at the small island 'Gospa od Skpjela', the only artificially built island in the Adriatic., Source: portmontenegro.com