The Gulf of Lion (French: golfe du Lion, Spanish: golfo de León, Italian: Golfo del Leone, Occitan: golf del/dau Leon, Catalan: golf del Lleó, Medieval Latin: sinus Leonis, mare Leonis, Classical Latin: sinus Gallicus) is a wide embayment of the Mediterranean coastline of Languedoc-Roussillon and Provence in France, reaching from the border with Catalonia in the west to Toulon.
The chief port on the gulf is Marseille. Toulon is another important port. The fishing industry in the gulf is based on hake (Merluccius merluccius), being bottom-trawled, long-lined and gill-netted and currently declining from over-fishing.
Rivers that empty into the gulf include the Tech, Têt, Aude, Orb, Hérault, Vidourle, and the Rhône.
The continental shelf is exposed here as a wide coastal plain, and the offshore terrain slopes rapidly to the Mediterranean's abyssal plain. Much of the coastline is composed of lagoons and salt marsh.
This is the area of the cold, blustery winds called the Mistral and the Tramontane.