Biskops-Arnö was a palatial residence of the archbishop of Uppsala, built in the first half of the 1300s. After the Reformation it was left to decay and finally demolished in the early 1700's, when the present main building was erected. For nearly 200 years Biskops-Arnö was a seat of Colonel in the Royal Regiment.
In 1956 Biskops-Arnö moved to the foundation of the Association of the Nordic Institute, who placed there a Nordic education institute and a college. Biskops-Arnö is a great destination that offers both nature and culture. Make sure to visit the Gothic hall, a room with limestone player and grand pillars - a remnant of the old bishop's castle. Visiting groups can book a meal or coffee at Biskops-Arnö college who also have hostel during the summer.
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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.