Felslabor Grimsel

Grimsel Test Site GTS

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: Mid-JUN to mid-OCT Tue-Fri 9-16. Tours only for groups and after appointment.
Fee: free
Classification: Underground laboratory
Light: LightIncandescent Electric Light System
Dimension: L=1,500 m, VR=450 m, A=1,730 m asl, T=13 °C, 3.5 m diamter tunnel system.
Guided tours: D=120 min, 150 min with crystal cave. (English Deutsch - German Français - French Japanese)
Address: 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.


1972 NAGRA founded.
1979 geological mapping of the area.
1980 horizontal exploration boreholes.
FEB-1982 decisions to construct the GTS made.
JUN-1982 contact with Kraftwerke Oberhasli AG (KWO).
NOV-1982 federal operation licence.
SEP-1983 arrival of full-face tunnel boring machine.
NOV-1983 first experiment on excavation effects.
20-JUN-1984 inauguration of GTS.
1983-1993 Phases I-III.
1994-1996 Phase IV.
1997-2004 Phase V.
2003-2013 Phase VI.


The Felslabor Grimsel (Grimsel Test Site GTS) is an underground laboratory established by the Swiss National Cooperative for the Disposal of Radioactive Waste. It is located underground inside the famous Grimsel granite. It was established for scientific research concerning the safe management and disposal of radioactive waste.

In Switzerland, the producers of this waste are responsible for its safe disposal. So the NAGRA is a joint venture of the Swiss Federal Government and half a dozen corporations which are involved in nuclear sciences. This institution established and manages several underground nuclear laboratories. This one is open to the public.

The laboratory is rather close to the hydro-electric electric power plant. The reason is easy: the power plant needed numerous underground tunnels, which were reduced to minimize costs of this laboratory. The site is not intended for the disposal of radioactive waste.