Erlach Abbey also known as St. Johannsen Abbey, was founded between 1093 and 1103 by Kuno, Count of Fenis and Bishop of Lausanne, on land that was then an island in the river Thielle. After Kuno's death, the abbey church was completed by his brother, Burchard, bishop of Basel. The new monastery was settled by monks from Saint Blaise Abbey. The Vogtei, initially the property of the Counts of Fenis, passed from them to the Counts of Neuchâtel-Nidau, and from them at the end of the 14th century to the city of Bern, which in took over the domain of Erlach in 1474, definitively acquiring it in 1476.
The abbey was secularised between 1528 and 1529. The nave of the abbey church was demolished, but the choir and transept remained to be used for grain storage. These structures were demolished in 1961 after they had become unsafe, but the choir was rebuilt between 1970 and 1971. The other buildings remained standing, and in the 19th century were put to various industrial uses, until in 1883 the Canton of Bern bought the site back and turned it into a prison. Since 1978, it has served as an adjustment centre for young men.References:
The Externsteine (Extern stones) is a distinctive sandstone rock formation located in the Teutoburg Forest, near the town of Horn-Bad Meinberg. The formation is a tor consisting of several tall, narrow columns of rock which rise abruptly from the surrounding wooded hills. Archaeological excavations have yielded some Upper Paleolithic stone tools dating to about 10,700 BC from 9,600 BC.
In a popular tradition going back to an idea proposed to Hermann Hamelmann in 1564, the Externsteine are identified as a sacred site of the pagan Saxons, and the location of the Irminsul (sacral pillar-like object in German paganism) idol reportedly destroyed by Charlemagne; there is however no archaeological evidence that would confirm the site's use during the relevant period.
The stones were used as the site of a hermitage in the Middle Ages, and by at least the high medieval period were the site of a Christian chapel. The Externsteine relief is a medieval depiction of the Descent from the Cross. It remains controversial whether the site was already used for Christian worship in the 8th to early 10th centuries.
The Externsteine gained prominence when Völkisch and nationalistic scholars took an interest in the late 19th and early 20th centuries. This interest peaked under the Nazi regime, when the Externsteine became a focus of nazi propaganda. Today, they remain a popular tourist destination and also continue to attract Neo-Pagans and Neo-Nazis.