Tourbillon Castle was built sometime between 1290 and 1308 by the Bishop of Sion, Boniface de Challant, as his principal residence. After Boniface died in 1308, his successor Aymon II de Châtillon probably finished the castle. In 1352 the Upper Valais revolted against Bishop Guichard Tavel. Led by Peter de la Tour, in November of that year, they marched on Sion, burned the town and unsuccessfully besieged the castle. In 1373, the Prince-Bishop bought Majorie Castle and moved his residence off the rocky spire. However, Bishop Tavel was not able to enjoy his new palace for long. In 1375 he was captured and murdered by rebels led by Peter's son, Anton de la Tour, in 1375.
Tourbillon became the Prince-Bishop's summer residence and remained a visible symbol of secular and ecclesiastical power. In 1384 a group of rebels attacked Sion and captured Tourbillon and Majoria. Bishop Eduard of Savoy had to request soldiers from Count Amadeus VII of Savoy and Bern to retake his castles.
A large part of the castle was destroyed during the Raron affair in 1417 and Bishop Wilhelm V of Raron had to flee to Bern. The castle was then rebuilt in the 1440s to 1450s by Bishop Guillaume VI of Raron. As part of the reconstruction, the chapel was repaired and painted with Gothic frescoes which are still visible. It remained the administrative center of the diocese but in later centuries the military importance of the castle decreased. On 24 May 1788, a gigantic fire in Sion reduced the castle to ashes. The Bishop planned to rebuilt Tourbillon, but the revolutions sweeping through Europe ended the plans. The castle was excavated and restored in the 20th century.
The castle ruins are located on a rocky spire above the city of Sion. Reaching the site requires climbing steep stairs that wind around the hill. The castle is surrounded by a ring wall that follows the irregular top of the spire. On the west side of the complex is a pentagonal fortified building. The 15th century chapel is located in the south-east corner. The chapel's frescoes are still intact despite the fire that destroyed the castle. A slender watch tower still stands in this corner as well. The southern wall is fortified with a square gate house. The keep is rectangular and many of the interior walls still stand.References:
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.