The hilly Parc Montsouris (on the Left Bank) and the Buttes-Chaumont (on the Right Bank) are more challenging.
Only those in good physical shape should try these.
mnli hypothesis: Only those in good physical shape should try these. premise: The hilly Parc Montsouris (on the Left Bank) and the Buttes-Chaumont (on the Right Bank) are more challenging.