The Quartier Latin has been the studious end of Paris for eight hundred years, and it wears two pasts at once: the bookshops of the Left Bank, and the Roman city of Lutetia buried just underneath. Three kilometres uphill and back, with both layers showing.
Start at Shakespeare and Company, the green-fronted English bookshop facing Notre-Dame, then a minute inland to Saint-Séverin for its spiralling palm-tree column. The Musée de Cluny is built straight over a Roman bath-house; the cold-room vault still stands, and The Lady and the Unicorn hangs upstairs — though it shuts on Mondays, so mind the day.
Then the climb. Rue Mouffetard runs downhill as a market street, best worked in the morning when the stalls are out; take it down, not up. The walk's quiet wonder is the Arènes de Lutèce, a Roman arena reached through an unmarked passage off rue Monge — boules players on a stadium floor most Parisians never find. Finish at the Panthéon on the hilltop, the view back over the quarter laid out below, and Place Monge a short drop away.
