Rarely do a capital's treasures line up so generously: a UNESCO medina around ancient Zitouna, Carthage that rivaled Rome on the seaside suburb, and artists' blue-white Sidi Bou Said — three civilizations on one TGM tram line. Add Bardo's world-greatest Roman mosaics, then descend to the Sousse-Hammamet coast. Pine-nut tea on a clifftop café is the ritual.