Tvrđava sv Ivan

The Saint Ivan Fortress features thick, curved stone walls that hug the sharp rocks of the harbor entrance. It functions as the southeastern anchor of Dubrovnik’s defensive system. In the sixteen hundreds, the Republic of Ragusa built a specialized wooden boom here. They stretched a massive iron chain across the harbor mouth to the opposite shore every night to block invading ships. When the wind howled or the sea surged, the chain rattled against the fortress stone, a sound that signaled the city was locked tight.