Meyersche Stollen

Useful Information

the water collector brings clear water.
Location: Aarau. Opposite the train station of Aarau go down the Poststraße. At the end on the right side, after the church, is a building which also belongs to the church. The entrance is down a stair and into the cellar.
Open: All year daily.
By appointment only.
Fee: For a group of up to 20 persons EUR 200.
Classification: SubterraneaWater Supply
Light: none, bring caving equipment
Dimension: L=2,000 m.
Guided tours: D=2 h.
Bibliography: Rainer Meng (1972): Die Mayerschen Stollen von Aarau, Aarauer Neujahrsblätter 1972, Verlag Sauerländer, Aarau 1972.
Anon (1997): Die Mayerschen Stollen von Aarau, Schweizerische Gesellschaft für Höhlenforschung, Sektion Lenzburg (SHG-L). Eigenverlag, Lenzburg 1997.
Address: IG Meyersche Stollen, Postfach 3367, 5001 Aarau. 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.


walls and arch supporting the soft rock.
1788 Mayer travels to Germany, to study at Göttingen and Freiberg.
1791 Mayer returns from Germany and soon takes over his fathers weaving mill.
1791 The father buys the area where the factory will be built later.
~1800 construction of the tunnels and the factory.
1803 Mayer asked to hand in an application.
1811 Mayer is the first who climbs the Jungfau.
1825 official year of death.
1830 factory sold to Friedrich Heinrich Feer.
1837 purchased by the church.
1938 during the renovation of the Feerhaus secret passage from the first floor into the cellar discovered.
1960s surveyed by Rainer Meng and some friends.
1982 construction of the new post destroyed the central part of the tunnels and the water wheel.
1992 start of guided tours by the Pfadi St. Georg Aarau.
1999 Interessengemeinschaft Meyersche Stollen, a non-profit organization which offers the tours.


typical passage profile.

The Meyerschen Stollen (Adits of Mayer) are named after their excentric but ingenious creator Johann Rudolf Meyer (*1768-✝1825). He was the son of a respectable Seidenbandweberei (silk ribbon weaving mill) owner from Aarau of the same name. He was rather wealthy and so he travelled between 1788 and 1791 to the universities of Göttingen and Freiberg in Germany. There he studied natural sciences, especially mining technologies. Freiberg in Saxony is a famous mining town until today.

Back in Aarau, Mayer was part of the beginning industrial revolution. Cheap woven goods from Great Britain's factories flooded the world market, and he as a Swiss factory owner had to develop or die. He planned to built a new factory and produce his silk ribbons with mechanical looms. What he needed was energy to power the looms, and steam energy was still very expensive. Water energy would be much better, but the use of the brook which ran through the city of Aarau and was a tributary to the big Aare river, was already distributed among other citizens. So he had the rather strange idea to use underground water instead of surface water.

The strange idea worked out, but it required a lot of work. A system of about 2,000 m of tunnels was constructed. One tunnel, the lowest, drained the water from the factory to the Aare river. A system of tunnels branching of in the opposite direction collected the groundwater. Right below the factory was a huge chamber which contained a 9.75 m diameter wooden water wheel, similar to the water wheels in the mines of the Harz. The power of the waterwheel was tranferred to the facory above where it worked the looms. It produced only between 3 and 4 horse powers, which is pretty low concering the enormous amount of work necessary to construct the tunnels. And it was necessary to dam the water in the upper tunnels over night in order to collect enough to last for the whole day. Unfortunately the damming had the bad effect that sometimes the cellars of houses above the tunnels were flooded.

ceiling with soda straws.

The construction of the tunnels was rather easy because of the softness of the clays and cherts. The miners started at the Aare river where a spring emerged at the foot of the river bank, below the city center of Aargau. They followed the water in the general direction of the new facory grounds. After they had dug a while, they blocked the water with a small dam, and then dug off material, mostly soft clay and cherts, which soon became mud in the water. When they opened the dam the mud was flushed out of the tunnel without further work. This simple technique reduced the workload pretty much and speeded the mining. But the soft rock was also dangerous, there was the problem of collapse. In order to make it safe, the tunnels had to be walled completely with bricks and mortar.

one of the few bigger chambers.

The whole construction, started probably soon after Mayer returned from Germany in 1791. It took numerous years, especially the collector tunnels were continued for some time. And is was done rather secretly. He told nobody what he was doing and never asked for permission. The workers were forced to be silent about the tunnels, he employed only foreign miners who afterwards moved away. If this was just paranoia is not clear, but the right to use water was very valuable and often fought for before the court. And unfortunately the drainage he had created reduced the amount of water in the Stadtbach brook above surface, which would have cause a trial if his neighbours knew. But it took several years until someone noticed the underground waterwheel. Floods after heavy rains caused the cellars of neighbours to be flooded, the water dammed in the the upper tunnels for the waterwheel flooded them.

In 1803 a complaint resulted in the official order to hand in an application for the use of the water. This would have caused official examination of the tunnels, probably a fee, and probably the allowance would not have been given. So he simply forgot to hand in the application. And as he was a famous politician, an important entrepreneur, employer, and tax payer, he was never forced to do it. The situation stayed as it was for decades, until his son finally handed in the application.

Mayer lived on the northern side of his factory area, in a house named Feerhaus, after his next owner. It is unclear when he died, the official year of his death is 1825, but this was defined 100 years after his death, because of the lack of official documents. Later some letters were found which suggest that he still lived in 1829.

The tunnels were underground, unnoticed for a long time. When the wooden wheel was not needed any more it started to decay. But the tunnels remained open all the time. During the early 1960s the tunnels were surveyed by Rainer Meng and some friends. In 1982 the Swiss Post constructed a new building, right on top of the water wheel. As a result the wheel chamber and the wheel were discovered and then destroyed to make the foundation of the building safe. The tunnell system was cut into two parts. A side entrance still existed in the Feerhaus beneath the church St. Georg, and subsequently the city of Aarau tried to survey the tunnels in order to make future development of the city save. Archaeologists explored the tunnels and started to make tours from the 1990s on. Later members of the boys scouts guided tours. Today the tours are organized by a non profit organization which was founded in 1999 by the people involved in the protection of the tunnels.

The tours start in the cellar of the Feerhaus, here is the possibility to change clothes. Old clothes, rubber boots, helmet, headlamp and gloves are very much recommended. Bring also fresh clothes to change afterwards. The tunnels are wet and full of clay and you will become dirty. However, there is no need to crawl, so you will normally not get soaked. A wash basin in the cellar allows to clean the clothes afterwards.

Meyersche Stollen Gallery