It lies at the extreme north end of the Adriatic, limited on the southwest by the easternmost point of the Po Delta in Italy and on the southeast by the southernmost point of the Istrian Peninsula in Croatia.

An area at the northeastern end of the gulf is sometimes distinguished as the Gulf of Trieste, informally defined as the part of the Adriatic northeast of a line between the southernmost point of Punta Tagliamento in Italy and the westernmost point of Savudrija or Punta Salvore in Croatia, an area of about 550 square kilometers (210 sq mi).

The Tagliamento, Piave, Adige, Isonzo, Dragonja, and Brenta Rivers flow into the Gulf of Venice.

The major cities along its coast are Venice, Trieste, Koper, Chioggia, and Pula.

The term was limited to the area around Venice as the Latin name for the sea became more common in English and among other European geographers.