Altdorf

Last weekend, Red Baron attended a 90th birthday party in Postbauer-Heng near Nuremberg.

A son of the jubilee, Gernot Arp, professor of geology and paleontology at Göttingen University, offered to take those interested on a geological excursion to the former university town of Altdorf. Nearby, there is a unique geological formation.

Altdorf in the Topographia Frankoniae 1648.
The university buildings are on the upper left.

When I hear the word Altdorf, I automatically think of William Tell, but Old Village is a common name in "German" lands.

Students at Altdorf University listen to their lecturer

Hadn't Wallenstein once studied in Altdorf, not far from the site of one of his greatest triumphs?

In August 1632, Gustaf Adolf had made himself at home in Nuremberg. Wallenstein had fortifications built on the hills on the north bank of the Rednitz near the Alte Veste in Zirndorf and waited until the Swedish king was forced to leave Nuremberg due to a lack of provisions.

Finally, on September 3, Gustaf Adolf sought a military decision. Again and again, he sent his troops to attack the well-entrenched imperial forces, but in vain.

Wallenstein wrote to his emperor, Ferdinand II, "The king has suffered a tremendous blow in this enterprise ... and although Your Majesty had valor and courage to spare before, this occasion has confirmed them even more, seeing how the king, having brought all his power to bear, has been repulsed, and the title of invictissimi belongs not to him but to Your Majesty." Well, Wallenstein kisses the but of his commander.

Gustav Adolf not only lost his aura of invincibility but also a third of his troops. Many of his mercenaries deserted and seamlessly joined Wallenstein's forces.

The university building in Altdorf

Gustaf Adolf fell in the Battle of Lützen in November 1632, and the University of Altdorf closed its doors in 1809 during the Napoleonic era.

The campus in 2026. Note: the fountain is still in place.

The main building of Altdorf’s former university is now a social-diaconal facility focused on people with disabilities, named after Johann Heinrich Wichern.

If you want something, you have to want it completely; half-heartedness is the same as nothing.

Wichern is widely known as the inventor of the Advent wreath.

But I digress.

Before we visited the geological site, we went to the Museum in Atdorf, which houses impressive fossils found during the excavation of the Ludwigskanal.

The Ludwigskanal at the Dörlbach incision near Altdorf

At the beginning of the 19th century, Bavarian King Ludwig I ordered the construction of an artificial waterway to be built between Kelheim on the Danube and Bamberg on the Main. The project started in 1836 and took 10 years to complete.

The idea of building a navigable connection between the Rhine and Main rivers and the Danube was not new. Common theories assume that Charlemagne, then still King of the Franks, had the so-called Fossa Carolina (also known as Karl's Ditch) built in 793.

The Dörlbach incision for the Ludwigskanal in 1845, with the old road bridge

The Ludwigskanal was 173 km long and had 100 locks. However, the ships were too small for mass transport, and soon the powerful railroad entered the market.

      

In 1950, the canal was abandoned after many sections had already been destroyed during World War II. In 1992, a modern Main-Danube Canal was inaugurated, but it proved uneconomical too and is now used only for tourist boat trips and water sports.

At the museum, Prof. Arp gave an introduction to Earth's history before our group admired the exhibit.

Timeline of Earth's history

A map in the museum shows the geological formation through which the Ludwigskanal was built.

Pachycormus,
the thick-bodied fish, lived in the time period of 189-60 million years ago

Ammonites

Ichtyosaur (Stenoteropterygius quadriscissus)

Ichthyosaurs are land animals that returned to the sea and transformed their limbs back into flippers. The number of finger joints and finger rays increased, especially between 182 and 174 million years ago.

Altdorf black marble

Black marble from Altdorf with its fossil inclusions was à la mode and correspondingly expensive.

According to the museum director, this tobacco box made from black marble is the “most expensive” item of the exhibition.

Geological cross-section through the terraced slope of the Dörlbach incision for the Ludwigkanal. 

Using a display board, Prof. Arp explained the geological situation of the Dörlbach incision.

Climate change, ocean currents, and mass extinction

The rock sequence cut into Dörbach reflects a striking shift from a cold, glaciated period to a warm period. The cause is believed to be the simultaneous strong volcanic activity in the southern hemisphere of the Earth and the resulting increase in atmospheric carbon dioxide. As temperatures rose, sea levels rose sharply, and ocean circulation decreased. This led to salt stratification in the water and ultimately to a lack of aeration of the sea floor. This was followed by species extinction and the formation of facies sludge in the Posidonia shale. 

Only the slow degradation of carbon dioxide over 2-3 million years and the further opening of the epicontinental sea to the Arctic led to gradual re-aeration and mixing with bottom-contacting ocean currents. Evidence of this can be found in so-called belemnite battlefields and a more species-rich bottom fauna in the Jurassic marl. (Gernot Arp, University of Göttingen).

(©James Albright)

The most impressive find during construction of the Ludwig Canal was a 1.5-meter-long ichthyosaur skull.

 

Tunnelling of the Ludwigskanal at Schwarzenbach (©Brunzerus/Wikipedia)

On our way back to Postbauer-Heng, we passed the tunnel at Schwarzenbach. What a technical achievement in the middle of the 19th century.

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