Caverna de las Brujas

The Caverna de las Brujas, the witches' cave, opens in a limestone ridge at around 1,800 metres in the cordillera south of Malargüe, formed by water dissolving marine rock laid down when this was seabed. Inside, a route of several hundred metres passes through chambers named for their shapes, with stalactites, stalagmites, columns, flowstone and delicate straw formations, some of them still growing. Visits are guided in small groups with helmets and lamps supplied, take around two hours underground, and involve crawling and scrambling in places; lights are switched off at one point to give a complete darkness few people have experienced. Numbers are limited to protect the formations, and bookings are made in Malargüe.

What you actually see

• The formation chambers - stalactites, columns and flowstone along the route.
• The total darkness - the moment when all lamps are turned off.
• The marine limestone - rock formed when the cordillera was under the sea.
• The mountain approach - the track climbing to the cave entrance.

When to go

October to April, when the access track is passable; snow closes it in winter. Tours run at fixed times and must be booked in Malargüe, often a day ahead in high season. The cave holds a constant cool temperature year-round.

Honest expectations

Entry without a licensed guide is not permitted. The route involves stooping, crawling and slippery rock, and is unsuitable for anyone with mobility problems or claustrophobia. The access track is rough gravel, and the round trip from Malargüe takes most of a day.

Nearby

Malargüe is the booking point; Las Leñas lies north and La Payunia east.