Paris in the 1920s ran on cheap rent, cheap drink and an improbable concentration of talent. Ernest Hemingway, F. Scott Fitzgerald, Gertrude Stein and Pablo Picasso all lived within walking distance of each other, and much of that geography survives if you know where to look. A self-guided route through the Latin Quarter, Montparnasse and Montmartre lets you see the city the way the expatriates did — on foot, one café at a time.

Start on the Left Bank at sunrise in the Jardin du Luxembourg, where Hemingway would meet Fitzgerald or walk dogs with Stein. Coffee and brioche on Rue Soufflot puts you in the shoes of Jake Barnes from The Sun Also Rises. A short detour brings you to 74 Rue du Cardinal Lemoine, where a plaque marks Hemingway's first Paris flat; the dive where he drank away his frustrations, the Café des Amateurs, still trades nearby — renamed Café Delmas.

Book lovers should head to 12 Rue de l'Odéon, the original site of Sylvia Beach's Shakespeare & Company, where Ulysses was first published and where Hemingway and Fitzgerald borrowed books on credit. The shop has since moved to 37 Rue de la Bûcherie by Notre Dame, queues and all. Lunch at Le Comptoir des Saints-Pères (under €25 with a drink) puts you on the exact spot of Michaud's, where Fitzgerald once asked Hemingway to check his 'measurements' in the bathroom after a bruising comment from Zelda. Gertrude Stein's legendary salon at 27 Rue de Fleurus — the nerve centre of the whole scene — is a 15-minute walk away.

Evenings belong to Boulevard du Montparnasse, which the expatriates single-handedly kept in business. Le Dôme and Le Select still thrive; the Dingo Bar, where Hemingway and Fitzgerald first met over champagne, is now the Auberge de Venise. The Closerie des Lilas remains a fine spot for eavesdropping, and Hemingway's old flat at 113 Rue Notre-Dame des Champs sits around the corner.

For Picasso, cross to Montmartre. Pass the site of the old Cirque Medrano on Boulevard de Rochechouart (commemorated with a mural of acrobats), climb to the artist's former studio at Place Émile-Goudeau, and lunch at Le Relais de la Butte, where Picasso and Stein once ate together. Views over the city, street musicians and a scrum for terrace seats in summer come free.

Beyond these districts, the trail continues: Fouquet's on Rue Laffitte still sells the honey cakes and nut candies Alice Toklas loved; the Ritz on Place Vendôme offers a Fitzgerald suite at a cool €13,700 a night; and Stein and Toklas lie buried at Père Lachaise. A century on, the city has tried to scrub away its boozy expat chapter — and largely failed. With a little imagination, it's all still there.