The bikes in the picture look more like the ones made by http://www.bakfiets.nl than the fietfabriek model (there are quite a lot of manufacturers in competition for this market). They handle well and are very stable to ride.

Kids do cycle and walk to school. It looks like this: http://nl.youtube.com/watch?v=2n_znwWroGM

As for temperate... It was -6 C ( 21 F ) for several days last winter and no-one stopped riding, and it hit 35 C ( 95 F ) in the summer this year, and that just meant that the bikes were ridden to the beach. And hills ? Having ridden in hilly places and here, I can assure you that the mighty headwinds that you get in a flat country are much worse than hills. You don't get to go back down the other side of a headwind. Note also that levels of cycling in Switzerland are significantly higher than the US or UK. Switzerland is anything but flat.

And how much are bikes ridden here ? Well, in this city the average person makes 1.2 cycle journeys per day.

As it is, I can accomplish bike commutes about half the time total, but the weather & terrain in the upper midwest just don't work in your favor. I'm guessing that's also the case in much of the rest of the US, although having an infrastructure built around a biking mindset would certainly help.

All the giant Dutch sit up and beg type.

I loved amsterdam for the bike culture, but i did no cycling.

I was in Denmark and cycled an almost identical bike from Helsingor to Copenhagen, which as much as I love them old style bikes was bloody hard work, they weigh a ton.

In DK the priority is as Fumbata said about Holland, people bikes cars.

There's a law that states if you in a car bang into a cyclist it is automatically your fault.

The emphasis is that if you are driving a car you are in charge of a deadly weapon and so should duisplay greater care.

which is absolutely bang on.

I've lived in Amsterdam, Netherlands for the last two years, and I have driven a car a grand total of 3 times since I've been here! I have a old rusty single-gear bicycle with a milk crate strapped to the front (for the dog to ride in) -it's the poor man's Bakfiet.

I'm absolutely in love with the Dutch cycling culture, and I wish it would take hold in more places around the world. Dutch people in general are fit, happy, and healthy, and I attribute a lot of that to riding bicycles instead of driving cars. I think there are basically 3 reasons why it works:

1. Dutch people have bicycling in their blood. Kids learn to ride bicycles just after they learn to walk (small wooden balance-bikes with no pedals). To this da, the Dutch are still pissed that the german occupants stole their bikes at the end of WW2 (never mind all the other Nazi atrocities!)

2. Lawmakers prioritize in this order: people, bikes, and THEN cars. There are just as many bike paths in this country as there are roads. Most urban centers do not allow cars at all. Parking is a nice to have, not a must have. (In contrast, in Atlanta several downtown bars were shut down a few years ago because they did not have the legally required amount of parking spaces - where's the logic in that?!)

3. As Zeytoun so aggresively mentioned, they keep bicycling fun and accessable to all. No helmets required, no fancy $1000 mountain bikes, no lycra shorts. Anything that even barely resembles a working bicycle is perfectly acceptable, and anyone is welcome to join in.

So maybe that's the recipe: more bikes for a healthier, happier population. Wouldn't it be nice if more cities/countries had the same approach?

also: for the stabilaty: tehre are also (more common in the Netherlands)3 wheeled variants. Google images for the word: "bakfiets" for examples.

Realize that the dutch do not wear helmets.

Then get a life.

The leading cause of death of American children is car accidents.

http://farm1.static.flickr.com/17/21313717_aadefea7fc.jpg?v=0

Probably not too common elsewhere given how much Portlanders love the bikes.