Johannisberg is a prominent ridge of the Wöllmisse, a Muschelkalk plateau east of Jena. The steeply sloping spur of land to the Saale Valley north of the district of Alt-Lobeda bears the remains of two important fortifications from the late Bronze Age and the early Middle Ages. Due to several archaeological excavations and finds recovered since the 1870s, they are among the few investigated fortifications from these periods in Thuringia. Of particular interest in archaeological and historical research is the early medieval castle. Due to its location directly on the eastern bank of the Saale, its dating and interpretation were and are strongly linked to considerations of the political-military eastern border of the Frankish empire. It is disputed whether it was a fortification of independent Slavic rulers or whether it was built under Frankish rule. According to a recent study, it may have been built in the second half of the 9th century in connection with the establishment of the limes sorabicus under Frankish influence.Grabolle 2007a; ders. 2007b; ders. 2008.
Topographical and geomorphological situation The Johannisberg is located north of Jena-Lobeda on the eastern bank of the Saale. Together with the Kernberg to the north and the Jena Hausberg, it forms the southeast front of the middle Saale near Jena. Its steep slopes are formed by the over 100 m thick lower Muschelkalk, popularly also called Wellenkalk, from which several solid limestone banks emerge (see also Geology of the Middle Saale Valley).
The Muschelkalk plateau of the Wöllmisse jumps out here with a boot-shaped spur far to the west. The Johannisberg with a height of 360–373 meters above sea level is limited in the north by the narrow Pennickental and in the south by the wide valley of the Roda. In the west it breaks off steeply, in the upper part almost vertically to the Saale Valley. The height difference is 215–220 m. It can be distinguished between a roughly trapezoidal plateau with 180 m of greatest length and 70 m of greatest width and the steeply sloping, ridge-shaped, northwest-facing peak with a length of about 200 m. To the east, the mountain, with an average width of 120 m, merges into the plateau of the Wöllmisse without any natural obstacle. There are two powerful springs in a small, deep water crack on the southern edge of the mountain, about 250 m south and 100 m below the plateau. North of the Johannisberg, the Pennickenbach flows in the valley about 140 m below.Grabolle, Johannisberg 2008, 11.
Description of the remains of the hillfort
Two main hillforts
Due to the steep drop to the south, west and north, the plateau of Johannisberg is naturally protected. It therefore lent itself to the construction of a fortified hilltop settlement in prehistory and the early Middle Ages. At the narrowest part of the spur, access was sealed off with constructions made of wood, stones and earth. Due to their decay, today they appear only as hillforts. Theses ones are clearly preserved in the terrain, differing in size and shape. The western hillfort is about 48 m long, 1.60 m high and a little curved inwards. It runs along the narrowest part of the plateau from its northern to its southern edge. At a distance of 28 m to the east is a second straight hillfort, about 80 m long, 1.30 m high.
Remains of the edge fortification
On the southern edge of the plateau, from the southern end of the western hillfort to the edge in the west, an approximately 35 m long, much lower hillfort has survived. A sketch from 1884 and a drawing from 1912 also show a hillfort at the transition from the trapezoidal plateau to the spur, where today only a clear terrain edge can be seen.Beide Zeichnungen in der Ortsakte Jena-Lobeda, Johannisberg, im Bereich für Ur- und Frühgeschichte der Friedrich-Schiller-Universität Jena According to the older plan, the plateau was even surrounded by hillforts on all sides. Probably the low hillfort is the remainder of an edge fortification, which was preserved on the somewhat less rugged steep slope to the south here.
Presumed rampages The existence of two further hillforts in the east adjoining apron is unclear. These are described in the older local history literature of the 1920s and 1930s„Bald bemerken wir, daß der Weg durch eine Senkung eines querlaufenden Erdwalles führt. Zu diesem laufen im gleichen Abstande noch zwei Wälle mit der gleichen Senke. Auch dem ungeübten Auge fallen diese gleichmäßigen, halbkreisförmigen Erdwälle auf, die einen Abschluß nach der Hochebene hin bilden“; John Grieshammer: Vorgeschichtliche Wallburgen auf Jenas Höhen. In: Der Pflüger. Monatsschrift für die Heimat 3, 1926, S. 20–25. – „Weiter vorgeschoben liegen die Überreste von noch zwei Wällen, wenn man sie als solche ansprechen darf“; Karl Kolesch: Vorgeschichtliche Wallanlagen in der Nähe Jenas. In: Altes und Neues aus der Heimat. Beilage zum Jenaer Volksblatt 1909–1920. Neudruck der 1. und 2. Folge, Jena 1939, p. 11. and are also recorded on the two drawings. While they are not mentioned in various publications by the excavator Gotthard Neumann in 1959 and 1960, Reinhard Spehr in 1994 spoke of a "straight line(s) of the two forewalls that had been overlooked so far."Spehr, Christianisierung 1994, S. 52 Anm. 34. Vgl. auch ders., Kirchberg 1997, pp. 37 Anm. 2 The entire area today has been heavily reshaped by extensive reforestation since the 1950s. Further encroachments were probably made by entrenchment works in connection with the foot drill and Manöverplatz of the Jena garrison, which was used until the First World War. Without archaeological investigations it cannot be decided whether the relatively flat and rather irregular ground undulations and incisions to the east of the two hillforts mentioned are natural, geological phenomena or actually artificially created or at least expanded fortifications.Vgl. Matthias Rupp: Die vier mittelalterlichen Wehranlagen auf dem Hausberg bei Jena. Städtische Museen, Jena 1995, , pp. 114 f. Anm. 145, der mit Verweis auf die Angaben von Spehr einschränkend bemerkt, dass die Vorwälle noch des sicheren archäologischen Nachweises entbehren. In the latter case, the site would be considerably enlarged once again.
Archaeological investigations on the Johannisberg
Excavations and finds recovery in the second half of the 19th century and the first half of the 20th century.
The clearly pronounced hillfort complex attracted interest early on. The first excavations and recoveries of read finds were carried out by the founder of prehistoric and early historical research in Jena, Friedrich Klopfleisch, in the 1870s and 80s. These excavations, which usually lasted only one day and were mostly carried out with students in the context of Sunday "Archäolog. Exkursionen in die Umgegend Jena's", some records and sketches exist in Klopfleisch's diaries. Finds were recovered in several places and at least one cut through a hillfort was made. However, the exact location of the excavation sites is not known. Further recoveries of read finds and unsystematic excavations were carried out in the first half of the 20th century by archaeological amateurs. For example, Walther Cartellieri, a son of the Jena professor of history Alexander Cartellieri, carried out investigations west of the western hillfort around 1912, as shown by a sketch he made of the Johannisberg with an entry of the site. In the 1930s, employees of the Germanic Museum of the University of Jena, including Gotthard Neumann in particular, were able to recover further reading finds and thus expand the museum's holdings.
Excavations under Gotthard Neumann 1957 and 1959 The excavations by Gotthard Neumann in 1957 and 1959 brought about a significant progress in knowledge. Within three weeks in 1957, a 76 m long and about 1 m wide cut I was made through both hillforts. Neumann recognized the eastern hillfort, over 80 m long, with the remains of two stone blind walls, as being of early medieval origin, while the western hillfort dates from the late Bronze Age. After the excavations were completed, the brothers A. and G. Daniel unsystematically recovered some more finds in the cut between the two hillforts. During the four-week excavation campaign in 1959, several small areas and cuts were uncovered at the foot of the hillfort and at the presumed entrance to the north. The investigated areas reached a total size of about 270 m2, of which 167 m2 were in only 1 m wide sections. In the excavation areas, apart from the fortification, hardly any clear features and no stratigraphy were recognizable. This is on the one hand due to the low thickness of the humus cover, on the other hand certainly also due to the excavation methodology of the narrow sections, in which large-scale structures are usually very difficult to recognize.
The excavation in 1980 by the Museum of Prehistory and Early History In August 1980, the Museum of Prehistory and Early History in Weimar conducted a one-week post-excavation under the direction of Sigrid Dušek. During this excavation, the area at the gate, which had already been investigated by Neumann, was uncovered again and extended, and another 4.90 × 2.10 meter area on the inner facing wall of the outer hillfort was investigated. The results remained unpublished and were only mentioned summarily in a few places in the literature.
Further investigations and finds recovery
In 1983 and 2002, further finds were deposited in the Museum Weimar, which could be picked up during the cultivation of the inner surface for the subsequent afforestation or recovered during a renovation of the inner blind wall. In spring and summer 2003, Tim Schüler of the Thuringian State Office for the Preservation of Monuments and Archaeology undertook geophysical measurements. An area of several square meters at the southern end of the plateau between the two hillforts was investigated using geomagnetics, and the absence of areal features was confirmed. In addition, a geoelectrical profile, also called a pseudo-profile, was made through the early medieval hillfort in the area of the current path, and two other pseudo-profiles were made through the remains of the edge hillfort in the southwest corner of the plateau.
In October 2003, the Department of Prehistory and Early History of the University of Jena was able to conduct a five-day follow-up investigation of the section through the early medieval hillfort made in 1959, in which the southern profile was moved back about half a meter and recorded again. This mostly confirmed Neumann's observations, but also modified them in some details.Ausführlich zu den genannten Ausgrabungen bei Grabolle, Johannisberg 2008, pp. 11–15.
Late Bronze Age settlement phase
Research history In the course of his excavations, Friedrich Klopfleisch was the first to recognize that Johannisberg had already been settled in prehistory and early history. He introduced the site to archaeological research in 1869. He dated the remains of the "einheimische(n) Töpferei", which in his view were made according to the "Vorbilde der römischen", initially to the "2.–4. Jahrhundert nach Chr."N.N., Dreissigste Generalversammlung. Naumburg am 2. und 3. Oktober. In: Zeitschrift für die gesammten Naturwissenschaften 34, 1869, pp. 345–361, hier p. 352. In 1880, finds from Johannisberg were represented at the first large "Exhibition of Prehistoric and Anthropological Finds of Germany" in Berlin, initiated by Rudolf Virchow.