8. New York City

The Big Apple has begun a huge initiative to make biking a priority, including a plan to encircle Manhattan with a greenway. April's Five Borough Bike Tour involved 30,000 (registered) riders and 42 miles of car-free cavorting. NYC is still the "leader" in bike theft, so bring a lock. New green bike lanes are adding visibility and, this being New York, controversy to the grid, so visitors shouldn't always expect courtesy from those behind the wheel. However, the NY-based Transportation Alternatives, the best pro-bike organization around, is working hard to change this attitude.

For more information: Bike New York