Kupa River Valley

The Kupa rises at Razloge in Gorski Kotar as a spring pool at the foot of a rock wall, deep, still and green, sitting in beech forest at the head of an otherwise dry valley - divers have gone down well over a hundred metres in it without finding the bottom of the system. From there the river runs east and then forms much of the border between Croatia and Slovenia, through a wooded valley with scattered villages, mills and swimming spots. The water is cold and clean enough for crayfish and trout. The valley road is narrow, slow and beautiful, and the settlements along it have been losing population for decades.

What you'll find

• A spring pool at the source - deep, green, at the foot of a rock wall.
• A system dived past a hundred metres - with no bottom found.
• The Slovenian border downstream - the river as the frontier.
• Emptying villages and old mills - along a narrow valley road.

When to go

May to September; the road is difficult in winter. A full day.

Things to know

The valley roads are narrow, winding and slow - distances take much longer than they look. Services are very thin. The source is a short walk from a parking area and can be busy on summer weekends. Swimming water is genuinely cold.

Nearby

Cabar is upstream; Delnice and the motorway are east.