Tunis runs on small money: the medina charges nothing to walk, a bowl of lablabi costs 4 TND, and the TGM train reaches Carthage and Sidi Bou Said for under a dinar. Three days based near Bab el Bhar rarely tops 60 TND a day.
The government square above the medina is open ground with no ticket booth: the ochre facade of Dar el Bey, the white marble clock tower, and a free downhill walk along Rue de la Kasbah toward Zaytouna's minaret.
The 1848 arch on Place de la Victoire marks the old boundary between Arab and colonial Tunis. East of it runs the ficus-shaded promenade past the 1897 Cathedral of St Vincent de Paul, free to enter, and the art nouveau Municipal Theatre.
Laid out in 1892 across 110 hilltop hectares, Tunis's big park climbs through eucalyptus and cypress to the 17th-century Koubba pavilion, a tiled open loggia with a terrace looking over the whole lake basin and the port.
Several carpet houses on the blanket souk let visitors climb to their roof terraces facing the Zaytouna minaret. There is no entry charge; buy a mint tea for around 3 TND and nobody rushes you off the parapet.
The 1891 iron-framed municipal market off Rue Charles de Gaulle: a wet fish hall, barrels of cured olives, harissa scooped by weight and stacked Deglet Nour dates. Bread, cheese and fruit for a full picnic runs under 8 TND.
A plain, long-running canteen a block off Bourguiba where office workers queue for a fixed three-course menu: salade méchouia or chorba, then couscous or grilled merguez, then fruit. Around 12-15 TND a head.
The medina's cheapest market, a warren of lanes north of Rue Djemaa Zitouna trading in imported textiles, household goods, spices and knock-off everything. Prices start low and haggling is expected rather than optional.
The square outside the medina's northern gate turns into an open-air kitchen after dark: lablabi with soaked bread and a poached egg for about 4 TND, brik à l'oeuf around 2 TND, fresh almond milk from carts.
Take the TGM light rail from Tunis Marine to Carthage Hannibal for around 0.7 TND, then climb to the Punic quarter on Byrsa: excavated houses, cisterns and a hilltop terrace over the Gulf of Tunis and Cap Bon.
Two lagoons below the hill are the remains of Carthage's military and commercial harbours, once berthing 220 warships. The shoreline path around them is unfenced and free, with fishermen and herons for company.
Two TGM stops on, the blue-and-white clifftop village costs nothing to walk. Climb Rue Habib Thameur past the studded doors to the lighthouse terrace, then drop down the stairs to the marina rather than the pricey café row.
The last TGM stop opens onto a long free public beach and a seafront promenade where Tunisois families walk at dusk. Kiosks sell fresh-squeezed juice and bambalouni doughnuts hot from the oil for a dinar or two.