Haslum church was built in c. 1190 in Romanesque style. It is possible that it was built by Cistercian monks who also built Halvard Cathedral in Oslo. The original long nave was altered to cross shape in the 1200s. In 1300 there were 12 altars in the church. Haslum church was reconstructed in 1853 and restored to the medieval appearance in 1924.
The wooden statues of the Virgin Mary and the Bishop are copies of medieval originals that have been moved to the Antiquities Collection at the University of Oslo. The Renaissance altarpiece (1631) and pulpit (1590-1642), as well as the baroque baptismal font (1736) are worth of seeing. The paintings on the ceiling were executed by Axel Revold in 1920.
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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.