The entrance to the gulf is through a 700 m (2,297 ft)-wide channel between Aktio (ancient Actium) on the south and Preveza on the north; a recent road tunnel connects the two.

The gulf is quite shallow, and its northern shore is broken by numerous marshes, large parts of which form an estuary system.

The Louros and Arachthos (or Arta) rivers drain into it; for this reason it is warmer and less salty than the Ionian, and a current flows from the gulf into the sea.

It is rich in grey mullet, sole, and eel, and is also very famous for the local variety of large shrimp (gabari, in Greek γάμπαρη).

The remains of numerous ancient cities lie on its shores: Nicopolis, Argos Ippatum, Limnaea, Preveza and Olpae.