The island area is about 80 acres. St. Cyricus is the only island off the Bulgarian Black Sea coast that is connected to the continent by a breakwater (artificial isthmus) built in 1927. This facility forms the Sozopol Bay as a horseshoe where water is calm even in the worst weather. St. Cyricus Island together with Stolets (Scamnium) peninsula are the oldest populated areas of Sozopol. There are suggestions that the ancient known temple of Apollo featuring a statue by Calamis was built on the island.