Apollonia was an ancient Greek city located on the right bank of the Vjosë river. Apollonia was founded in 588 BCE by Greek colonists from Corfu and Corinth, on a site where native Illyrian tribes lived, and was perhaps the most important of the several classical towns known as Apollonia.
Apollonia flourished under Roman rule and was noted by Cicero in his Philippicae as magna urbs et gravis, a great and important city. Christianity was established in the city at an early stage, and bishops from Apollonia were present during the First Council of Ephesus (431) and the Council of Chalcedon (451).
Its decline, however, began in the 3rd century AD, when an earthquake changed the path of the Aoös, causing the harbour to silt up and the inland area to become a malaria-ridden swamp. The city became increasingly uninhabitable as the inland swamp expanded, and the nearby settlement of Avlona (modern-day Vlorë) became dominant. By the end of antiquity, the city was largely depopulated, hosting only a small Christian community. This community (which probably is part of the site of the old city) built on a nearby hill the church of the Dormition of the Theotokos, part of the Ardenica Monastery.
References:Visby Cathedral (also known as St. Mary’s Church) is the only survived medieval church in Visby. It was originally built for German merchants and inaugurated in 1225. Around the year 1350 the church was enlarged and converted into a basilica. The two-storey magazine was also added then above the nave as a warehouse for merchants.
Following the Reformation, the church was transformed into a parish church for the town of Visby. All other churches were abandoned. Shortly after the Reformation, in 1572, Gotland was made into its own Diocese, and the church designated its cathedral.
There is not much left of the original interior. The font is made of local red marble in the 13th century. The pulpit was made in Lübeck in 1684. There are 400 graves under the church floor.