The town's historic sites include the central Romanesque-Gothic Cathedral of St Mark (built from 1301 to 1806), the 15th-century Franciscan monastery with a Venetian Gothic cloister, the civic council chambers, the palace of the former Venetian governors, grand 15th- and 16th-century palaces of the local merchant nobles, and the massive city fortifications.

In 1541, the Ragusans asked for the separation of ecclesiastical jurisdiction over Ston, which they had conquered, from Cursola, which in the previous century had become a Venetian possession.

[8] The architecture of Korčula is represented by many well-preserved buildings such as churches, palaces, piazzas, and towers.

Along with the construction of stone walls surrounding the city, 12 towers were erected throughout the Middle Ages to provide protection for the town.

One of the great architectural pieces of the town is St. Mark's Cathedral which is located at the highest point of the peninsula.

The devout Catholic inhabitants of Korčula keep alive old folk church ceremonies and a weapon dance, the Moreška, which dates back to the Middle Ages.