and the Council of Chalcedon (451). It was mentioned in the 6th century Synecdemus of Hyerocles among the 20 cities of the Illyrian provinces, as part of Epirus Nova. 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. Legacy Apollonia has not been inhabited after its 4th century AD abandonment, with the exception of a monastery. As such, 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. At the monastery a Greek language school was operating at 1684 which provided also 'higher education' that time. A school still existed at 1880 but with a limited number of students. In June 2020, part of the site was vandalized by unknown individuals. Two columns were knocked down, resulting in the almost complete collapse of the Nymphaeum. According to the site's director, the damage might be "irreparable" and likely occurred during the COVID-19 lockdown. The incident was condemned by Albanian archeologists and the President of Albania, Ilir Meta. Archaeology The city seems to have sunk with the rise of Vlora. It was "rediscovered" by European classicists in the 18th century, though it was not until the Austrian occupation of 1916–1918 that the site was investigated by archaeologists. Their work was continued by a French team between 1924 and 1938. Parts of the site were damaged during the Second World War. After the war, an Albanian team undertook further work from 1948 onwards, although much of the site remains unexcavated to this day. In 1967, the archaeological site was seriously and irrevocably damaged by heavy machinery and the building of c. 400 concrete military bunkers at and near the ancient polis. Some of the team's archeological discoveries are on display within the monastery, known as the Museum of Apollonia (opened in 1958) and other artifacts from Apollonia are in the capital Tirana. Unfortunately, during the anarchy that followed the collapse of the communist party in 1990 and reversion to capitalism, the