Above the compact town centre reigns St. George’s Cathedral, which gives the city its special character. It was probably built in the 12th century, but no exact data in this regard exists.

In the 14th century, it was built to its present size. In the year 1344, on the Day of St. George, the cathedral was consecrated by nine bishops from near and far. It acquired its present appearance after Baroque renovation in the year 1637. The Bell Tower was completed in 1608, and the Baptistery in the year 1650. During these years, reinforcements were made to the hill on which the cathedral rests.

The supporting walls were built in the year 1641, and on the sea side, the hill was fortified with stone arches. The construction of the stone arches began in the year 1663 and lasted until 1804. They were seriously dilapidated due to the effects of erosion, and thus had to be reconstructed and restored in 1998.

Among the important pieces of the cathedral’s property is the church organ, made by Petar Nakić, a Franciscan monk from Dalmatia. After his theology studies in Venice, he was trained in organ making and in the year 1729 completely dedicated himself to this craft. His organ in Piran was installed in the year 1746 and had 16 ranks. Unfortunately, it was damaged and had to go through a series of restorations.

During World War I, it was severely damaged. All the larger pipes were removed to be melted into weapons. Almost 100 years before that, its keyboard in the manual was changed by A.V. Rossi from Trieste. In the year 1936, it was reconstructed by G. Bencz, but he did not restore the original disposition. In the year 1956, several adjustments were made by V. Rebolj, and so the set up of the organ today considerably varies from the original.