glacier potholes
bring earth’s
history to life

The glacier potholes bear witness to the fact that during the last Ice Age, 20,000 years ago, the region of Lucerne was covered by a thick layer of ice. Even older are the fossilised shells and palm fronds which were found in today's Glacier Garden – they show that 20 million years ago, Lucerne lay on a subtropical seashore. Such witnesses to Earth's history make the Glacier Garden a geotope of national importance.

DISCOVERY OF THE NATURAL MONUMENT

A NATURAL
WONDER
stops a
wine cellar

Josef Wilhelm Amrein-Troller was intending to build a wine cellar in the Lucerne sandstone when he discovered the potholes under the meadow on November 2, 1872.

At the time, Lucerne was emerging as a popular destination for tourism. So, instead of a wine cellar, Amrein opened the Glacier Garden on May 1, 1873. Then followed, in 1874, the residence in the style of a Swiss house, which today houses the museum. The natural monument has been covered by a tent-roof since 1980, which protects it from the elements and air pollution.

FORMATION OF THE NATURAL MONUMENT

THE ICE AGE
LEAVES TRACES
IN THE
SANDSTONE

The geological bedrock of the Glacier Garden is made of what is known as Lucerne sandstone.

The area of today's Glacier Garden is dominated by a rocky mogul. As the Reuss Glacier moved across it during the last Ice Age, the typical characteristics of a so-called "roche moutonée" were left behind: glacial polish, glacial striation, crescentic gouging, deep potholes and glacial boulders bear witness to the time when Lucerne lay under around 800 metres of ice.



HOW ARE GLACIER POTHOLES FORMED?

The potholes were formed at the bottom of the glacier by the sheer force of the melt water, which carried sand and gravel. It seeped through fissures to the bottom of the glacier. As the flow of water gathered speed, vortices of up to 200 km/h began to form. Within a few years, or perhaps even in one single summer, potholes had been eroded. The largest glacier pothole in the Glacier Garden is 9.5 metres deep, with a diameter of 8 metres.

EROSION OF THE SANDSTONE

The slow-moving flow of the glacier over thousands of years abraded and polished the sandstone bedrock. Glacier polish, glacier striation and crescentic gouging testify to this.

WHERE DO THE BOULDERS COME FROM?
These stones either fell onto the glacier surface in the Alps or were scooped up from the ground by the ice and transported further down the valley. The boulders provide evidence that the alpine foothills were once almost entirely covered by glaciers. The large, light-coloured granite boulder from the Gotthard region weighs around 5 tons.

FORMATION OF THE NATURAL MONUMENT

WHEN
LuCernE
STILL HAD A
PALM BEACH

Yes, Lucerne was once a seashore lined with palm trees: fossilised seashells and palm fronds which were found in the Lucerne sandstone, together with traces left by heavy storms, testify to this.

further MUSEUM HIGHLIGHTS:

PARK

stroll
through
the alpine
garden

Follow the rocks and discover the prehistory of the Alps! Get a magical look at the Gorner Glacier from right in the middle of the city! And climb up to the observation tower and discover the Pilatus!


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SWISS HOUSE

EXPERIENCE
THE ALPINE
collection
of wonders

Where the founder of the Glacier Garden once lived, you will now find fascinating historical testimony about the prehistory of the Alps, as well as information on measuring them and their formation.


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MIRROR MAZE

WHO CAN
FIND THEIR
WAY OUT OF 
THE MAZE?

The exotic Mirror Maze dates from the end of the 1800s and is an attraction from the early days of tourism that remains as fascinating as it is bewildering.


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