A short drive south takes us into a totally different landscape: Slovenia's Karst region — a high, fertile, and windblown plateau. Since the limestone upon which everything around here sits is easily dissolved by water, the Karst is honeycombed with a vast network of caves and underground rivers. The most dramatic cave to tour is Škocjan. Guides tell the story as, drip by drip, stalactites grow from spaghetti-thin strands to mighty sequoia-like stone pillars. While there's little reason to go inside, the castle makes an ideal spot for a scenic drink — and a great capper for our visit to the Karst region.