The Walls of Ston are a series of defensive stone walls located in Croatia, stretching approximately 5.5 kilometers. Built in the 14th century, they were constructed to protect the nearby town of Ston and its valuable salt pans from invaders. The walls are notable for their impressive height and strategic design, featuring numerous towers and fortifications. These walls are part of a larger fortification system that includes the Ston Fortress and the Korčula Fortress. The Walls of Ston are often regarded as one of the longest defensive walls in Europe, showcasing the architectural skills of the time and the importance of salt production in the region.