Tunisia is situated on the Mediterranean coast of North Africa. It is bordered by Algeria to the west and Libya to the southeast.  Here's the map.

Diving in Tunisia is generally shore-based and centered around the tourist towns of Tabarka, Cap Bon and Hammamet. There is a WWII wreck to discover off the coast of Hammamet, colourful underwater fauna in Hergla, underwater archaeological sites in Mahdia, hidden caves and colourful fish in Djerba, as well as beautiful grouper fish near Port El Kantaoui.

• Tabarka - superb diving.  Tunnels Reef covers 500m and contains approximately 20 tunnels you can swim through.
• Cap Bon - the northern coast and the Cap Bon, being rocky and steep, open up to deep waters.  Visibility is excellent here but it is for experienced divers only.  The sites are varied and rich in Mediterranean fish varieties: groupers, murenes, gorgonians, coral, mullets, octopuses.
• Hammamet - a number of wrecks, several of them dating from WW2 including German and Italian vessels. Some still have their cargo - jeeps and motorcycles.

• The Algaz wreck at 65m (a technical dive).  It is very likely that there are WW2 wrecks all along the coast reflecting the wartime activity which saw many troop and equipment carriers landing in North Africa.
• Grouper Rock - does what it says on the tin; the groupers here are protected and fed so close up encounters are common.
• The Takrouna, at Hammamet, a WW2 german destroyer.  Much of its annuminition, guns and cargo remain.

• International languages are not spoken; Arabic and French are common but English, Spanish, Italian and German are rarities among dive guides.
• There are probably not enough diving in Tunisia to warrant a specific diving holiday.