The Château de Chaumont, Loire Valley, France
The castle was founded in the 10th century.
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 accept the Château de Chaumont in exchange for the Château de Chenonceau which Henry had given to de Poitiers.