Zitadelle Petersberg
About This Site
The Zitadelle Petersberg rises above Erfurt's old town, one of the largest baroque town fortresses of central Europe and the only one largely preserved; laid out as a star, it was held to be the most modern fortress of its day and impregnable.[1] The Elector of Mainz had it built from 1665 as a stronghold against the city; Prussia and France later held it, and today its core of about twelve hectares, with eight bastions and some two kilometres of walls, houses state offices, homes, the Federal Labour Court and places to visit.[2]
A royal hill and a Benedictine abbey, 852–1181
Long before the fortress, the Petersberg was a place of kings: Louis the German held a court diet here in 852, King Henry I a diet in 936 at which his son Otto was proposed for election, and Emperor Otto II stayed on the hill in 973, 974 and 975. In 1060 Archbishop Siegfried I of Mainz founded the Benedictine monastery of St Peter and Paul, whose life on the hill lasted 743 years, until 1803. On 16 June 1147 Archbishop Henry I of Mainz consecrated its church, and at the imperial diet of 1181 Henry the Lion, Duke of Bavaria and Saxony, submitted to Emperor Frederick Barbarossa here.[3] Until the end of the thirteenth century many imperial and royal diets and synods met at the monastery.[4]
A stronghold against the city, 1648–1665
The Peace of Westphalia in 1648 gave Erfurt back to the Electorate of Mainz. The city resisted and was placed under the imperial ban, until an army of 15,000 soldiers from Mainz and France forced it to give in, and Erfurt became a provincial town directly under the Elector. To prevent further uprisings and as a shield against the Protestant powers, Elector and Archbishop Johann Philipp von Schönborn had a citadel built on the Petersberg; Christoph Bernhard von Galen, Bishop of Münster, probably took part in planning it.[2] The hill had been fortified once before, when Gustavus Adolphus of Sweden chose Erfurt as his residence in 1631.[3]
Bastions, gate and listening tunnels, 1665–1702
The foundation stone was laid on 1 June 1665 for what was first called the Citadelle Johann Philippsburg. By about 1669, farmers from Erfurt doing forced labour and Italian stonemasons under the engineer Wilhelm Schneider had built the four bastions facing the town, Martin, Philipp, Leonhard and Kilian, together with the Peterstor and the Kommandantenhaus after designs by Antonio Petrini. Countermines, the Horchgänge, ran along the foot of the new walls, where soldiers patrolled to detect enemy miners in a siege. Between 1675 and 1700 followed the bastions Johann, Michael, Gabriel and Franz, three barracks and the ravelins Anselm and Lothar. Only after almost forty years, in 1702, was the fortress enclosed on all sides; a Mainz garrison of 500 to 800 men lived in its barracks.[2]
Welsch's outworks and a costly century, 1707–1802
When the Swedes threatened the northern lands of the Electorate in the Great Northern War, Mainz engaged the fortress architect Johann Maximilian von Welsch, who on Vauban's model strengthened the outworks and the defence of the ditches: two lunettes, the ravelins Wilhelm and Peter in 1708, a hornwork before the Bastion Gabriel between 1725 and 1728, a great ditch with palisades, a guardhouse in 1735 and two gun casemates, finished in 1737. In the 1770s the cost of upkeep led Mainz to consider razing the fortress, but the War of the Bavarian Succession of 1778 and 1779 changed minds, and it was kept in use with makeshift repairs.[2]
Prussians, Napoleon and the siege, 1802–1814
Prussian troops occupied Erfurt and the Petersberg in June 1802, and in March 1803 the monastery was dissolved to make room for a larger garrison. After the defeat at Jena and Auerstedt on 14 October 1806, parts of the Prussian army fled into the citadel and surrendered to Napoleon's troops the next day. Napoleon came to Erfurt on 23 June 1807 and visited the fortress then and during the Congress of Erfurt in 1808, with Tsar Alexander I. In 1813 the French prepared for a siege and stored supplies in the Peterskirche; on 6 November Austrian, Russian and Prussian batteries opened fire, and the monastery buildings, parts of the Peterskirche and many houses below the hill burned. The French held on until 5 May 1814, when General d'Alton handed the citadel peacefully to the Prussians and his 1,700 soldiers marched to Strasbourg.[2]
A Prussian fortress, 1815–1873
The Congress of Vienna gave Erfurt to Prussia, and the city was to become a fortress of the first rank with its two citadels. Gun caponiers were built between 1823 and 1825, and between 1828 and 1831 the Defensionskaserne rose on the site of the destroyed monastery.[2] The Peterskirche became a military supply store in 1820: its towers were pulled down, its upper walls reduced to the height of the aisles and three storage floors built inside.[4] A peace-time powder magazine of 1822 is the only one of its kind preserved in Germany. On 20 June 1873 Emperor Wilhelm I ordered the fortress to be given up, but for lack of money only the ravelins Peter and Wilhelm, the hornwork and the cavaliers along the walls were removed.[2]
Barracks, a court martial and a memorial, 1912–1995
The Hornwerkkaserne was built in 1912 and 1913, and the Defensionskaserne received a neo-baroque mansard roof that made it part of Erfurt's city crown. From 1940 the Wehrmacht's court martial 409 sat in the Kommandantenhaus; it sentenced about fifty deserters to death and had them shot near the place where their memorial stands today. The countermines gained new entrances on the town side to shelter citizens in air raids, and on 12 April 1945 American troops occupied the citadel. In the GDR the barracks served the police and the army, until the city took the Petersberg over in 1963 and opened parts of it to the public. In 1995 the artist Thomas Nicolai created the memorial to the unknown Wehrmacht deserter before the Bastion Philipp: eight steles, one stepping out of line, with Günter Eich's words Seid Sand, nicht das Öl im Getriebe der Welt.[2]
Restoration and new uses, since 1990
With the change of 1989 and 1990 the city set up a works yard on the Petersberg and began restoring the long-neglected buildings, laying out a circular path at the foot and along the crown of the walls.[2] It has been restored with great care and effort since 1990.[1] The Thuringian State Office for Monument Preservation and Archaeology has had its seat in the artillery barracks since 1993, the Federal Labour Court has worked since 1999 in a new building by Gesine Weinmiller on the former hornwork, and the Petersbergfest has been held on the old parade ground since 2000.[2] With about 550,000 visitors a year the Petersberg is among Erfurt's most visited sights, and for the Federal Garden Show of 2021 the city renewed its access and upper plateau.[5]
The Peterskirche, 1103 to today
The former church of St Peter and Paul, a three-aisled Romanesque basilica 75 metres long, is considered the first large building of the Hirsau school in Thuringia; built between 1103 and 1147, it shaped the city's skyline for centuries with its east towers beside the cathedral and St. Severus.[4] More recent research dates the great building from 1127; for the garden show of 2021 the Stiftung Thüringer Schlösser und Gärten had five million euros to clean and conserve its finely jointed ashlar walls and to open up its ground floor.[6] From April to November it now shows the exhibition Paradiesgärten – Gartenparadiese on garden art in Thuringia from the Middle Ages to the twentieth century, including the gardens of the monastery itself; a virtual-reality tour of about ninety minutes takes visitors back to the Petersberg of 1181.[7]
Walls, lift and views, today
The fortress's walls run for about two kilometres and stand 8 to 23 metres high, and a sentry path of the Mainz garrison, with a parapet and look-out bays at the bastion tips, leads almost all the way around them.[2] Visitors can explore the new exhibition in the Kommandantenhaus and the listening tunnels in the fortress walls, or simply enjoy the view over the old town. A lift on the fortress wall climbs to the upper plateau, and the panorama path from the Domplatz reaches the citadel without further aids.[1]
Questions visitors ask
- When was the Zitadelle Petersberg built?
- The foundation stone was laid on 1 June 1665; after almost forty years, in 1702, the fortress was enclosed on all sides, and its outworks were extended until 1737.[2]
- Why was the Petersberg fortress built?
- After Erfurt had resisted its return to the Electorate of Mainz in 1648, Elector Johann Philipp von Schönborn had the citadel built to prevent further uprisings and to guard against the Protestant powers.[2]
- What can visitors see at the Petersberg today?
- The exhibition in the Kommandantenhaus, the listening tunnels in the walls and the view over the old town;[1] from April to November the Peterskirche shows an exhibition on Thuringian garden art.[7]
- How do I get up the Petersberg?
- A lift on the fortress wall runs to the upper plateau, and the panorama path starts at the Domplatz.[1]
- Did Napoleon visit the Petersberg?
- Yes. He came to Erfurt on 23 June 1807 and visited the fortress then and during the Congress of Erfurt in 1808, accompanied by Tsar Alexander I; his troops held the citadel until May 1814.[2]
- What does the exhibition in the Peterskirche cost?
- 8 euros, reduced 4 euros; a combined ticket for the Peterskirche and the Kommandantenhaus costs 12 euros, sold at the visitor centre opposite, Petersberg 3.[7]
Sources (7)
- Zitadelle Petersberg — Stadt Erfurt, retrieved 13 September 2026
- Zitadelle Petersberg — Wikipedia, retrieved 13 September 2026
- Die Geschichte der Citadelle Petersberg — Freunde der Citadelle Petersberg zu Erfurt e. V., retrieved 13 September 2026
- Ehemalige Klosterkirche St. Peter und Paul — Stadt Erfurt, retrieved 13 September 2026
- Petersberg – ein Projekt der Buga 2021 — Stadt Erfurt, retrieved 13 September 2026
- Instandsetzungsarbeiten an der Erfurter Peterskirche — Stadt Erfurt, retrieved 13 September 2026
- Ausstellung „Paradiesgärten – Gartenparadiese“ — Stiftung Thüringer Schlösser und Gärten, retrieved 13 September 2026
Visit Information
Peterskirche exhibition: 8 euros, reduced 4, after 5 pm 4 euros, family ticket from 16 euros; combined ticket Peterskirche and Kommandantenhaus 12 euros.
Peterskirche exhibition, 1 April–1 November 2026: Tuesday–Sunday 10:00–18:00 (last entry 17:30). Tickets at the visitor centre, Petersberg 3.
Petersberg 3, 99084 Erfurt
In the history of Erfurt
Historic sites
Domplatz, Erfurt
The bombardment of the Petersberg fortress in November 1813 destroyed the quarter on the northern part of the square, which has been open ground ever since.
In Weimar's history
From 27 September to 14 October 1808 Napoleon and Tsar Alexander I met in Erfurt with the princes of the Rhine Confederation — and on 6 October the congress came to Weimar.
During the Congress of Erfurt in 1808 Napoleon visited the fortress on the Petersberg, accompanied by Tsar Alexander I.
Around Weimar
20 km West
The baroque citadel on the hill above the old town, built from 1665 for the Elector of Mainz and restored since 1990, with the Romanesque Peterskirche and a view across the city.