Château
The term comes from French-speaking regions and is used most often for buildings in these regions. Where clarification is needed, a fortified château (that is, a castle) is called a château fort. But the word is not used in the same way as  "castle" is in English, and most châteaux are more appropriately described as "palaces" or "country houses" in English than as "castles". For example, the Château de Versailles is so called because it was in the country when it was built, but it does not bear any resemblance to a castle, so it is usually known in English as the Palace of Versailles.The Château de Montsoreau is the first Renaissance château to have been built in France, in the world famous Loire Valley. The Château de Montsoreau is also the only one to have been built in the Loire riverbed.