The Castle of Sant Joan is a historic fortress located in Tossa de Mar, a coastal town in Catalonia, Spain. Built in the 12th century, it served as a defensive structure to protect the area from invasions. The castle features impressive stone walls and towers, offering panoramic views of the surrounding landscape and the Mediterranean Sea. Visitors can explore the castle's ruins, which include a well-preserved watchtower and remnants of the original walls. The site is a popular tourist attraction, providing insight into the region's medieval history and architecture. The Castle of Sant Joan is a symbol of Tossa de Mar's rich cultural heritage.