Krizna Jama

Križna jama is not run like a show cave. There is no lighting and no concrete path: visitors carry lamps, put on boots and are rowed in inflatable boats across a chain of underground lakes separated by calcite dams, of which twenty-two are known. The cave holds one of the richest cave bear bone deposits found anywhere, and a pile of skulls is left in place along the route. Numbers are capped hard and tours must be booked in advance.

What you actually see

• The lake chain - underground lakes separated by calcite dams, crossed by boat.
• The bear bones - cave bear remains left in place, including a pile of skulls.
• The lamp-lit visit - no fixed lighting, with visitors carrying their own lamps.
• The unaltered passage - a cave without concrete paths or installed infrastructure.

When to go

Year round at a steady eight degrees; boots and warm clothing are provided or required. Booking well ahead is essential because numbers are capped. High water after heavy rain can cancel tours.

Honest expectations

It must be booked in advance and turning up on the day does not work. The long tour is four hours, wet and cold, and not suitable for small children or anyone unsteady. Photography is restricted to protect the deposits.

Nearby

Lake Cerknica is northwest, and Rakov Skocjan is west.