Tripolitania
A historical region of northern Africa bordering on the Mediterranean Sea, Tripolitania is now part of northwestern Libya. Colonized by the Phoenicians in the 7th century BC, it was named for its three chief cities, Leptis Magna, Oea, originally known as Tripoli, and Sabratha, which are now must sees on any visit to this region.
Tripolitania is the most popular of the three regions, with almost 80 percent of the country's five million people. It is located in the northwestern part of the country and covers an area of approximately 140,000 square miles (365,000 sq. km). Bordered on the north by the Mediterranean Sea, its boundaries stretch east to the Gulf of Sidra and Cyrenaica, west to Tunisia and south into the Saharan Desert, where it adjoins the Fezzan. Having visited the old medina in Tripoli, drive some 85 miles east to Leptis Magna, a truly magnificent ancient Phoenician emporium. Following this, drive approximately one hour west of Tripoli to Sabratha, with its small museum, fine mosaics, sculptures and spectacular reconstructed Roman Theatre, let alone its magnificent coastal location, it is well worth a visit.
Alternative Suggestions
The Sahara
Stretching from south of Ghadames covering Libya's southwest quarter. 
Ghadhames
Famous for its desert architecture.