Café Saf-Saf is the obvious place to stop in La Marsa. It is set around an old draw-well under an enormous saf-saf (a kind of fig tree) that gives the café its name, and the courtyard is shaded, cool, and entirely characteristic of old Tunisia. The mint tea is good, the orange-blossom-flavoured pastries are better, and the place has been visited by everyone from Tunisian intellectuals to French colonial-era writers — Flaubert reputedly stopped here on his Tunisian travels.
The café is now firmly on the tourist map, and prices reflect that, but it is still a genuinely pleasant place to spend an hour. Live oud and bouzouki musicians sometimes play in the evenings. The café also serves simple Tunisian food at lunchtime — couscous, brik, grilled lamb — although the quality is uneven and you eat here for the setting rather than the menu.