Cycling in London is a risky, stressful, but actually quite exciting affair. In Amsterdam it's far different, as a cyclist you are in the majority by a large margin, and feel safe. Cars crawl along, because the streets are so small and there are always bikes and walkers clogging them.
In London you park your bike where you can, but most fences and railings have warnings that any parked bikes will be confiscated. In Amsterdam bikes are chained three, four or five deep on any immovable object. They're also left unlocked, standing up in the middle of pavements and roads. Shops have their own bike racks, the new American Apparel store in Amsterdam has its own branded rack outside.
So, to be bike-friendly takes more than painting a bike lane down the road and not even punishing drivers who plough through it. It takes lanes with physical barriers between it and the road, it takes shops who cater for, rather than punish, those who leave cycles outside. And it takes a government who protects cyclists, and punishes drivers who put them in jeopardy. :: Grist