Porrentruy Castle is a historic fortress located in the town of Porrentruy, in the Ajoie region of Switzerland. Built in the 13th century, it served as a residence for the local nobility and played a significant role in the region's history. The castle features impressive architecture, including thick stone walls and a distinctive round tower. Today, Porrentruy Castle is a popular tourist attraction, offering visitors a glimpse into the past. The site includes a museum that showcases artifacts and exhibits related to the castle's history and the surrounding area, making it an important cultural landmark in Switzerland.