The Château de Grignan is a historic castle located in the town of Grignan in the Drôme department of southeastern France. Originally built in the 12th century, it has undergone several renovations over the years, particularly during the Renaissance. The castle is known for its impressive architecture and beautiful gardens, which attract many visitors each year. One of the most notable features of the château is its connection to the famous French writer Madame de Sévigné, who frequently corresponded with her daughter, Françoise de Grignan, while living there. Today, the château serves as a museum, showcasing its rich history and the literary legacy of its past residents.