The ancient city, which the Greeks called Apsoros, was already surrounded by mighty walls in the Iron Age.
It was so important to the Romans that they dug a canal next to it that separates the islands of Cres and Lošinj to this day.
From early Christianity to the 19th century, Osor was the seat of the diocese, and in the Middle Ages, the important Benedictine abbey of St. Peter was built here, which, according to tradition, was founded by the Bishop of Osor St. Gaudentius.
The ancient capital of the Cres-Lošinj archipelago has long been a town-museum, and although it numbers only 28 inhabitants today, it still captivates with its beauty engraved in every stone.