No helmets for European cyclists

[roadie7]

We spent two weeks on a river cruise down the Rhine from Basal, Switzerland to Amsterdam and then by bus through Brussels and finished in Paris. In total we visited about 6-7 cities. I was particularly amazed at the swam of bicycles in Amsterdam; something you won't see in the US. However, I was shocked that, among the thousands of cyclists in Amsterdam, no one wore a helmet. I saw a few more helmeted cyclists in Paris but not even close to the number of Americans who wear a helmet.

I was wondering why so few cyclists in Europe. What do you think?