There was originally a Roman castellum (Castellum Laurum) in Woerden, as part of the limes of the Roman Empire and thus part of the defense lines of the northern border of the Roman Empire. The first castellum was built in the 40s AD, and was destroyed in 69 AD during the Batavian rebellion. In 70 AD the castellum was rebuilt, and the Romans remained until 402 AD, with an interruption lasting from about 275-300 AD. The Castellum was located at the present site of the medieval Petruschurch and surrounding church yard. During construction work on a new underground parking facility in the city center of Woerden, the remains of numerous old Roman buildings and a Roman cargo ship were found.
The current castle was built in around 1160 by bishop Godfrey van Rhenen. Due to its strategic location on the border between the County of Holland and the Bishopric of Utrecht, various wars have been fought in and around Woerden. In 1410 John III, Duke of Bavaria-Straubing reconstructed the castle.
Until the 19th century the castle was used as a prison. There's even a pit prison in the northwest tower, which was used for unruly prisoners. In the 20th century the castle was part of military barracks and used for storage of all kinds of goods but poorly maintained. This caused severe decay. Today it is restored as a restaurant.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.