by tgm
This is the metropolitan train service, Métro Léger de Tunis. Tickets are less than one dinar and service is frequent, but busy during rush hour. The station is located a few hundred metres to the east of the clock tower and the raised Trans-African Highway No. 1 directly east from the main drag Avenue Habib Bourgouiba; the one with the main Medina gate - just keep walking away from the Medina. The station is impossible to miss - it's a large building parallel to the road on the south side. Note that if you're heading out this way, there is also a national tourism office on the north-east side of the clock tower that effectively demarcates the edge of Tunis' larger buildings before the highway, and they provide free maps and advice regarding Tunis and Tunisia.
Carthage, famously razed by the Romans with the few remnants now safely encased in a museum, easily reached by train. Get the TGM from east of the clock tower
La Marsa, a beach-side settlement at the end of the TGM train line, just north of Sidi Bou Saïd
Sidi Bou Saïd, a lovely village of white-and-blue houses and fancy cafés and restaurants, easily reached by train