Air pollution in cities is a major environmental problem. Yet many car journeys in cities could easily be made by bicycle - IF the cycling infrastructure was good enough. In Copenhagen 36 per cent of the population commute to school or work by bicycle.
Under a programme to make Copenhagen the world's best city for cycling, more and wider bicycle lanes are being built, as are dedicated car-free bridges across the river.
Joyce Ohajah visits Copenhagen to see what it is like to travel in a city built for bicycles, and experience Bicycle Rush Hour, when more than 35,000 cyclists cross the Dronning Louises Bridge on what is the busiest bicycle street in the western world.