Wewelsburg castle is perched atop a wooded slope close to Paderborn's airport. The fortification Wifilisburg was used during the 9th and 10th centuries against the Hungarians. The next castle was demolished in 1123/24 by revolting peasants. From 1301 to 1589, the Prince-Bishops of Paderborn assigned the estate to miscellaneous liege lords.
The masonry of both predecessor buildings was integrated in the current triangular Renaissance castle. In its current form, the Wewelsburg was built from 1603 to 1609 as secondary residence for the Prince-Bishops of Paderborn. Wewelsburg was taken several times during the Thirty Years' War. In 1646 it was occupied and then razed by Swedish troops – namely by the army commanded by General Carl Gustav Wrangel. After 1650, the mostly destroyed castle was rebuilt by Prince-Bishop Theodor Adolf von der Recke and his successor Ferdinand von Fürstenberg. He carried out some architectural changes; the three towers of the castle got their Baroque style domes.
During the Seven Years' War (1756–1763), the basement rooms were probably used as a military prison. In the 18th and 19th centuries the castle fell progressively into ruin. In 1802, during German mediatisation the castle came into the possession of the Prussian state . On 11 January 1815, the North Tower was gutted by a fire that was started by a lightning strike; only the outer walls remained. From 1832 to 1934, a rectory existed in the eastern part of the south wing of the castle.
In 1924, the castle became the property of the district of Büren and was changed into a cultural center. By 1925, the castle had been renovated into a local museum, banquet hall, restaurant and youth hostel. During the Nazi regime Wewelsburg was used a school for SS organisation, focusing to pseudo-scientific research in the fields of Germanic pre- and early history, medieval history, folklore and genealogy.
Today Wewelsburg hosts a Historical Museum of the Prince Bishopric of Paderborn, Wewelsburg 1933-1945 Memorial Museum and temporary exhibitions.
The Château de Chaumont was founded in the 10th century by Odo I, Count of Blois. The purpose was to protect his lands from attacks from his feudal rivals, Fulk Nerra, Count of Anjou. On his behalf the Norman Gelduin received it, improved it and held it as his own. His great-niece Denise de Fougère, having married Sulpice d'Amboise, passed the château into the Amboise family for five centuries.
Pierre d'Amboise unsuccessfully rebelled against King Louis XI and his property was confiscated, and the castle was dismantled on royal order in 1465. It was later rebuilt by Charles I d'Amboise from 1465–1475 and then finished by his son, Charles II d'Amboise de Chaumont from 1498–1510, with help from his uncle, Cardinal Georges d'Amboise; some Renaissance features were to be seen in buildings that retained their overall medieval appearance. The château was acquired by Catherine de Medici in 1550. There she entertained numerous astrologers, among them Nostradamus. When her husband, Henry II, died in 1559 she forced his mistress, Diane de Poitiers, to exchange Château de Chaumont for Château de Chenonceau which Henry had given to de Poitiers. Diane de Poitiers only lived at Chaumont for a short while.
Later Chaumont has changed hands several times. Paul de Beauvilliers bought the château in 1699, modernized some of its interiors and decorated it with sufficient grandeur to house the duc d'Anjou on his way to become king of Spain in 1700. Monsieur Bertin demolished the north wing to open the house towards the river view in the modern fashion.
In 1750, Jacques-Donatien Le Ray purchased the castle as a country home where he established a glassmaking and pottery factory. He was considered the French "Father of the American Revolution" because he loved America. However, in 1789, the new French Revolutionary Government seized Le Ray's assets, including his beloved Château de Chaumont.
The castle has been classified as a Monument historique since 1840 by the French Ministry of Culture. The Château de Chaumont is currently a museum and every year hosts a Garden Festival from April to October where contemporary garden designers display their work in an English-style garden.