Pucher eliminates factors like climate and topography as explanations for cycling's far greater presence in European than in North American transportation, and says that even longer average U.S. urban trip distances cannot account for the dramatic gulf.

Pucher's argument is: "In short, bicycling has been thriving precisely in those countries that have adopted policies to make bicycling faster, safer and more convenient. Bicycle use has been falling in those countries that that have been neglecting the needs of bicyclists."

The article examines in detail how western German cities have nurtured bicycle use. Pucher says the German examples are in fact more interesting than those of Danish and Dutch cities because cycling was not particularly prominent in Germany in the 1970s, and the big cycling increases since then have come about alongside rapid suburbanization and the second highest (after the U.S.) rate of car ownership in the world.

Among German cities, as in many countries, university towns have the highest rates of cycling (though the article notes that one reason for this is strong representation by the Green Party in such municipalities' local governments, and that cycling has increased in spite of cheap student passes to very good transit systems). But even in major cities like Munich (Germany's 3rd largest), cycling's share is 15% of all trips.

Germany's most extensive bicycle systems consist of elements like:

· Bicycle path networks reaching all major commercial and residential areas. These are generally separated from traffic and feature ample sign systems and color-coded route plans.

· Traffic calmed local street networks that slow and circuitously route car traffic while providing easy, direct access for cyclists. Many cities with high cycling levels also have policies that restrict urban parking and highway capacity supplies.

· "Bicycle streets" that permit auto traffic but are designed to give priority to bikes - others are one-way for cars but have 2-way bikeways.

· Traffic signals that give intersection priority to bikes.

· Strong public education on bike safety and the many personal, social and environmental benefits of cycling.

· Adequate parking facilities of scale that varies from large central bike parking depots to wide coverage of low capacity on-street parking racks.