Short answers, pulled from the story.
The Adriatic Sea sits on the Apulian or Adriatic Microplate between the Italian and Balkan Peninsulas. It extends from the Gulf of Trieste in the north to the Strait of Otranto connecting with the Ionian Sea in the south.
Limestone deposits started forming across the region during the Middle and Late Triassic periods when the Adriatic Microplate separated from the African Plate. The plate moved northward and northeastward during the Eocene and early Oligocene epochs contributing to mountain-building processes.
The Northern Adriatic rarely exceeds 100 meters in depth while the Central Adriatic contains the Middle Adriatic Pit also called the Pomo Depression or Jabuka Pit. The Southern Adriatic Basin connects to the South Adriatic Pit through the Palagruža Sill.
Italy borders the western coast while Croatia Slovenia Montenegro Albania Bosnia-Herzegovina and Serbia surround the eastern and southern shores. Italy hosts the largest number of tourist overnight stays along the Adriatic coastline.
Roman naval bases like Brundisium and Dyrrachium became primary routes for trade and troop movements starting around 246 BC. Republic Venice gained maritime power receiving Byzantine tax exemption in 1082 before losing Dalmatia following the Treaty Turin in 1381.
The last major tuna catch was made in 1954 by fishermen from Santa Croce Contovello Barcola after increasing fishing prevented migration of large fish schools northward. Overfishing has since become a recognized problem affecting 450 species living in the Adriatic Sea.