Nantes, France

Green grid: Brittany isn't just butter and salty caramel: Its urban hub, Nantes, a world leader in weaning people off cars, has green credentials that go back nearly 200 years. Nantes claims to have invented the concept of public transit with a local omnibus service established in 1826, and it was the first French city to introduce low-impact tramways in the 1980s. Panoramic windows in the trams are ideal for sightseeing, particularly around the medieval city center, where automobiles are banned. Car-sharing and bike-rental schemes, as well as waste-reduction workshops for citizens, are also in place to help the city halve its carbon output by 2025.

Living city: Downtown Nantes is best explored on foot, skipping from stone rampart to crêperie as you make your way from the Castle of the Dukes of Brittany to the historic district's many cathedrals. From the city center, you can walk or take a short tram ride to the Jardin des Plantes, where 19th-century greenhouses contain 11,000 plant species.

Sustainable stay: The 46-room La Pérouse hotel, located downtown, was designed in 1993 with eco-efficiency in mind and a modernist aesthetic inside. The hotel provides guests with public transit tickets and cleans its rooms with organic products.

La Pérouse
3 Allée Duquesne
Tel: 33 2 40 89 75 00

Next: Prior planning in Portland, Oregon >