Coastal forts are military structures built along coastlines to protect against naval attacks and invasions. They often feature thick walls, towers, and strategic positioning to monitor sea traffic. These forts were crucial during times of war, serving as bases for artillery and troops. Many coastal forts were constructed during the 16th century to the 19th century, reflecting advancements in military architecture and technology. Famous examples include Fort Sumter in the United States and Fort Saint Elmo in Malta. Today, many of these forts are preserved as historical sites, attracting tourists and history enthusiasts.