In 2008, Fatih Hodžic proposed that Atlantis had been in the Adriatic Sea at the Southern Adriatic Basin. Further, he contended that Atlantis had been destroyed by an asteroid impact, and that this impact is recorded in Greek mythology as Phaëton. He proposes that the point of impact was either the Ionian or the Tyrrhenian Sea, west of Sicily. Additionally, Hodžic contends that the Pillars of Hercules were at the Strait of Otranto. However, Hodžic’s most contentious claim is that the approximately 70,000 stone blocks found across Bosnia and the surrounding regions, known as Stećaks, are remnants of structures from Atlantis. Currently, all historical and archaeological evidence of these stones prove that they date from medieval times and originate with the Catholic Church and some Islamic orders.
The Adriatic Sea separates the Italian Peninsula from the Balkan peninsula and the Apennine Mountains from the Dinaric Alps and adjacent ranges. The Adriatic is the northernmost arm of the Mediterranean Sea, extending from the Strait of Otranto (where it connects to the Ionian Sea) to the northwest and the Po Valley. The countries with coasts on the Adriatic are Italy, Croatia, Albania, Montenegro, Bosnia-Herzegovina, and Slovenia. The Adriatic contains over 1,300 islands, mostly located along its eastern, Croatian, coast. It is divided into three basins, the northern being the shallowest and the southern being the deepest, with a maximum depth of 1,233 metres (4,045 ft). The Otranto Sill, an underwater ridge, is located at the border between the Adriatic and Ionian Seas.
The Adriatic Sea sits on the Apulian or Adriatic Microplate, which separated from the African Plate in the Mesozoic era. The plate's movement contributed to the formation of the surrounding mountain chains and Apennine tectonic uplift after its collision with the Eurasian plate. In the Late Oligocene, the Apennine Peninsula first formed, separating the Adriatic Basin from the rest of the Mediterranean.
The origins of the name Adriatic are linked to the Etruscan settlement of Adria, which probably derives its name from the Illyrian adur meaning water or sea. In classical antiquity, the sea was known as Mare Adriaticum (Mare Hadriaticum, also sometimes simplified to Adria) or, less frequently, as Mare Superum, "[the] upper sea".
Settlements along the Adriatic dating to between 6100 and 5900 BCE appear in Albania and Dalmatia on the eastern coast, related to the Cardium Pottery Culture. During classical antiquity, Illyrians inhabited the eastern Adriatic coast, and the western coast was inhabited by the peoples of Ancient Italy, mainly Etruscans, before the Roman Republic's rise. Greek colonisation of the Adriatic dates back to the 7th and 6th centuries BCE when Epidamnos and Apollonia were founded. The Greeks soon expanded further north establishing several cities, including Epidaurus, Black Corcyra, Issa and Ancona, with trade established as far north as the Po River delta, where the emporion (trading station) of Adria was founded.
Roman economic and military influence in the region began to grow with the creation by 246 BCE of a major naval base at Brundisium (now Brindisi), which was established to bar Carthaginian ships from the Adriatic during the Punic Wars. This led to conflict with the Illyrians, who lived in a collection of semi-Hellenized kingdoms that covered much of the Balkans and controlled the eastern shore of the sea, resulting in the Illyrian Wars from 229–168 BCE. The initial Roman intervention in 229 BCE, motivated in part by a desire to suppress Illyrian piracy in the Adriatic, marked the first time that the Roman navy crossed that sea to launch a military campaign. Those wars ended with the eastern shore becoming a province of the Roman Republic.