Plitvice Lakes National Park

Sixteen terraced lakes, joined by waterfalls and cascades, in a forested valley in central Croatia. The water is a remarkable turquoise and green, and wooden boardwalks take you over and right beside the falls. It's a UNESCO World Heritage Site and Croatia's most famous natural sight.

There are several marked routes, from 2 to 8 hours, using electric boats across the largest lake, Kozjak, and a panoramic train. Start early to beat the tour groups: in summer the boardwalks get very crowded by late morning. Tickets cost much more in summer and must be bought online for a set entry time. Swimming isn't allowed.

The lakes are beautiful in every season, including in autumn colour or frozen in winter. Buses run from Zagreb (about 2 to 2.5 hours) and Zadar, or stay overnight in one of the villages nearby.