“Hello, over there in Albania!”, my kayaking guide Gigo shouts across the water as he paddles along effortlessly. He doesn’t really need to shout, because although we’re in Montenegro, we’re only a few metres away from the Albanians. We’re on the Buna (Bunë) River, a 40km stretch of water which divides the countries and is so tranquil that every sound is amplified, from the dip of our paddles to the rousing tones of the Muslim call to prayer.