Mid conference excursion: Historic city of Erfurt and citadel Petersberg

Thursday, 22th May 2008
Time frame: 14:30 - 18:00.
Excursion guides: Sascha Abendroth, Rebecca Dennhöfer, André Hölzer, Anita Kirmer, Rüdiger Kirsten, Martin Kümmerling, Norbert Müller, Horst Schumacher, Jan-Tobias Welzel

Erfurt was founded 742 A.C. at the Gera river. On our tour we will demonstrate the biodiversity of urban wildlife and wildflowers in the medieval city centre of Erfurt, examples of ecological design and river restoration along the green corridor of the Gera river, biodiversity of ornamental plants in urban front gardens and the recently restored and designed green spaces at the Petersberg citadel.

The tour by foot will start at the conference venue (Kaisersaal), pass the Merchant’s Bridge that is the longest inhabited bridge in northern Europe and will lead along the green corridor of the Gera. By this way we will pass the medieval and Wilhelminian styled settlement of the city. Finally we will climb on the citadel Petersberg which is located on a hill, where we will have a wonderful city panorama. On the way back we will pass the fish market square with its renaissance style houses and neo-Gothic Town Hall, the old quarter with lovely restored small framework residential houses and the Cathedral Square.

Historic city of Erfurt: Krämerbrücke (Merchant’s Bridge), the largest inhabited bridge in northern Europe.

Wilhelminian style front garden.

Fischmarkt (fish market) with neo-Gothic city hall.

In early times, the Petersberg was used as a place of worship and refuge. It served as a site for a Franconian castle and the St. Peter and Paul Benedictine monastery after which the Petersberg was named. The citadel was built between 1664 and 1707 and reflects the European style of fortress construction. Under the supervision of an Italian master builder, Antonio Petrini, four mighty bastions and the gatehouse with a baroque portal were erected in only three years. Emperor Napoleon Bonaparte had the citadel strengthened in 1812-13. From November 1813 to May 1814, it had to fulfil its defensive task only one single time by withstanding the Prussian besiegers, who were far superior in numbers to the French garrisoned in the citadel. From 1816 to 1868 the citadel was reinforced according to the neo-Prussian art of fortification design. From this period resulted the new guardhouse, the defensive barracks, gunpowder stores, caponnières, wells and a war-time bake-house with bombproof covering.

Along the Gera river a public green corridor was recently designed and combined with ecological river restoration

Citadel Petersberg, recently restored gatehouse with baroque portal.

Citadel Petersberg, Cymbalaria muralis was introduced to Germany for ornamental purposes by the Romans before 2000 years. Today it is a typical wildflower in ancient walls.

The restoration of the baroque Fortress has been one of the most costly and complex but also undoubtedly one of the most worthwhile preservation projects of our times. The priority was to preserve and develop the fortress site with its numerous testimonies to architectural and cultural history. Of particular importance was also the preservation of characteristic plant and animal communities in selected areas. In this regard, near-natural parts like urban woodland, woodland fringes, spontaneous ruderal vegetation and walls are of special interest.

Until now, in the Petersberg area, 175 vascular plants and 468 animals have been recorded. Particularly noteworthy are the bats that inhabited the underground passageways. Other endangered species are concentrated within the woodlands as well as the dry grasslands and walls with southern aspect. Two woodland sites of 2.2 ha and three wall sections of 608 m length had been designated as a “protected landscape element”. The nature protection sites are part of the protected cultural monument Petersberg Citadel. They belong to a net of urban biotopes that connect urban plant and animal species with the surrounding landscape.