Cours Julien is a gently sloping square in the 6th arrondissement — the bohemian centre of Marseille and the gathering place for its artists, musicians, students, and anyone who finds the Vieux-Port too polished. It's not a monument or a sight; it's a place where the city goes to sit outside and stay up late.
The square is lined with bars and restaurants with terraces that fill from late afternoon onwards. The streets radiating off it — Rue Crudère, Rue des Trois Mages, Rue d'Aubagne — are covered in commissioned murals by local and international street artists; this is one of the densest concentrations of street art in France, none of it curated, all of it changing. Walk around for twenty minutes and you'll find pieces in wildly different styles layered over each other on the same wall.
La Mauvaise Réputation is the best bookshop on the square; record shops and vintage clothing stores fill the neighbouring streets. Espace Julien, a few minutes' walk east, is the main live music venue for the neighbourhood and one of the city's best mid-size stages.
The nearby Place Jean Jaurès — known as La Plaine — extends the social scene eastward, with a Tuesday, Thursday, and Saturday market by day and tables spilling out of bars across the paving stones by night. Restaurants on both squares tend to be affordable, local, and good: Moroccan, Vietnamese, West African, and French bistros that change their menus weekly.
Cours Julien starts late and stays late. Nothing really happens before ten in the evening.