Arnhem Cave

Arnhem Cave runs for around four and a half kilometres through dolomite on a farm east of Windhoek, making it the longest known cave in Namibia. It was discovered in 1930 and has never been developed: there is no lighting, no walkways and no handrails, and visitors go in with helmets and lamps behind a guide from the farm. Six bat species roost inside, including two that occur nowhere else in the country, and the cave floor is deep in guano in places.

What you actually see

• The passages - four and a half kilometres of dolomite cave, the country's longest.
• The bat colonies - six species roosting, two of them found nowhere else in Namibia.
• The undeveloped interior - no lighting, walkways or handrails anywhere.
• The dust and guano - deep deposits on the floor through much of the system.

When to go

March to October is the cooler window and more comfortable for the drive. Tours run from the farm and must be arranged in advance. Cave temperature is constant year round.

Honest expectations

The cave is dusty enough that a mask is worth having and clothes will be ruined. Sections involve crawling and it is not for anyone claustrophobic. Access is only with the farm's guide and must be booked.

Nearby

Windhoek is west, and the Kalahari runs east.