Kristallkluft Gerstenegg

Useful Information

Location: At the Grimsel Pass. From Guttannen to Gerstenegg at the dam Räterichsboden. Turn right to the cable car. The entrance to the adit is at the cable car station. (N 46°33'43", E 8°20'41")
Open: Only in combination with Grimsel Test Site GTS or Grimsel2 Power Station
GTS: mid-JUN to mid-OCT Tue-Fri 9-16.
Kraftwerk Grimsel 2: JUN to OCT Mon-Wed, Sun afternoon.
Tours only for groups and after appointment.
Fee: GTS: free.
Kraftwerk Grimsel 2: Adults CHF 25, Children (7-18) CHF 20. Groups: first 20 persons CHF 150, additional persons CHF 5.
Classification: SpeleologyFracture Cave, Power station
Light: electric
Dimension: L=20m.
Guided tours: GTS: D=150min (English Deutsch - German Français - French Japanese)
Kraftwerk Grimsel 2: D=90min.
Bibliography: H.A. Stalder, E. Rufibach, D. Forter und P. Vollenweider (1987): Die geschützte Mineralkluft an der Gerstenegg, Grimsel BE,
Ernst Rufibach (1999): Freuden und Leiden im Leben eines Strahlers und Bergführers,
Address: KWO, Kraftwerke Oberhasli AG, 3862 Innertkirchen, Tel: +41-33-9822011, Fax: +41-33-9822005. E-mail: contact
Felslabor Grimsel, Nagra (Nationale Genossenschaft für die Lagerung radioaktiver Abfälle), Hardstr. 73, 5430 Wettingen, Tel: +41-56-4371111. Renate Spitznagel, Tel: +41-56-4371111, Tel: +41-56-4371282, Fax: +41-56-4371282, E-mail: contact
As far as we know this information was accurate when it was published (see years in brackets), but may have changed since then.
Please check rates and details directly with the companies in question if you need more recent info.


1974 discovered.


This is probably the most exceptional natural cave of the world. It is the only accessible crystal cleft filled with quartz crystals. It is located inside the Grimsel granite massive.

The cave was formed by tectonic forces and movements which are part of the orogeny of the Alps. In an early stage of the orogeny a magma intrusion into clefts caused by the folding cooled down very slow inside the mountains. The result was granite, where the three main components, quartz, spar and glimmer become solid each at its own temperature. So they are separated forming rather huge crystals. Later this intrusion was fractured by the teconic forces, after it became hard enough to be brittle. This cracks were filled by ground water. The granite, still containing some of its original temperature heated the water and induced thermal convection streams. The water dissolved quartz from the granite, transported it to this large cleft and redeposited the quartz in the form of continually growing quartz crystals.