A city of the Pheonician and Punic periods from the C6th BC it was the base of a powerful trading empire spanning the entire south Mediterranean and home to a population of the order of half a million people. Its most famous general was Hannibal who crossed the Alps to battle with the Romans. Hannibal suffered his first significant defeat defending the city against Imperial Rome in 146BC and it was completely destroyed. The site was developed by the Romans a century later and Carthage became the capital of the Roman province of Africa. A UNESCO World Heritage List site.
Take the TGM light rail line from Tunis to Carthage-Hannibal station.
Walk. The area is large and sightseeing is sweaty work on a hot day.
Very little remains of Carthage today, and Punic Carthage in particular was completely obliterated.
Antonin Baths. Ruins of the largest Roman baths outside Rome itself.
Carthage Museum. Most remnants excavated from the ruins have been stored in this cavernous museum located on Byrsa Hill, documenting both the Punic and the Roman era. Open 8:30 AM to 5:30 PM daily (until 7 PM in the summer), entry TD 4.2.
Acropolium (St Louis Cathedral) on top of Byrsa hill. Completed in 1890.
World War II North Africa American Cemetery and Memorial,  Just north of Carthage, a five minute walk from the Amilcar Station. Open daily except for December 25 and January 1; 9:00 a.m. to 5:00 p.m. The Cemetery is the final resting place for 2,841 American military Dead lost during the War in North Africa. A monument is inscribed with the names of 3,724 Americans whose remains were never found or idetified. The the memorial court contains large maps in mosaic and ceramic depicting operations across Africa. Free.