The Gulf of Gabes, also known as Lesser Syrtis, contrasting with the Greater Syrtis in Libya, is a gulf on Tunisia's east coast in the Mediterranean Sea, off North Africa. The gulf roughly spans the coast from Sfax to Djerba. At the head of the gulf is the city of Gabès (Ghannouche) where the tides have a large range of up to 2.1 m at spring tides. Both Gabès and Sfax are major ports on the gulf, supporting sponge and tuna fisheries, with Gabès being the economic and administrative center.

The Gulf of Sidra (Arabic: خليج السدرة, romanized: Khalij as-Sidra, also known as the Gulf of Sirte (Arabic: خليج سرت, romanized: Khalij Surt, is a body of water in the Mediterranean Sea on the northern coast of Libya, named after the oil port of Sidra or the city of Sirte. It was also historically known as the Great Sirte or Greater Syrtis.