The Château de Châteaubriant is a historic castle located in the town of Châteaubriant, in the Loire-Atlantique department of France. Originally built in the 11th century, it has undergone several renovations and expansions over the centuries, showcasing a mix of architectural styles, including Gothic and Renaissance elements. The castle is surrounded by beautiful gardens and offers stunning views of the surrounding landscape. The château played a significant role in French history, serving as a residence for various noble families. It is also known for its connection to Diane de Poitiers, a prominent figure in the court of King Henry II. Today, the château is open to the public, allowing visitors to explore its rich history and impressive architecture.