Plitvice Lakes National Park of Croatia

Our next selection is largely unknown to tourists from the United States, and perhaps that makes it even more precious. The limestone caves of the Plitvice Lakes National Park make the water of its 16 lakes and a handful of waterfalls shimmer brilliant shades of turquoise, silver and green. And to get a better view the lakes' beauty, you'll find a web of wooden plank walkways scattered throughout. But note that there is no true best or worst season to stop by this site in central Croatia. Snow and ice transforms the area into a winter wonderland; in summer the surrounding trees further enhance the hues of the lake water. If at all possible, though, avoid the onslaught of local tourists in July and August.