They do things differently in the Netherlands where to can cycle from Rotterdam to Nijmegen more or less on a dedicated Fietspad [cycle-path] a lot of it along the top of the dijks separating the River Maas/Rijn/Waal from the roads and farmland below. In all the major cities, the three main users of the streets - pedo velo auto - have their designated space. Where possible cars are separated from bikes by little kerbs or plantings of bushes. It is cycle-heaven. Of course this is helped by the fact that most of the Netherlands is flat as a pankoek. But it took a huge political and economic re-think to achieve this two-wheel nirvana.
the infra-structure of many Dutch cities was stretched or smashed to accommodate all the vehicles, market squares became car-parks, roads were widened and a comprehensive system of motorways was constructed to link all the major population centres at home and abroad. If you had a car, you could aspire to a home with a neat garden in the suburbs. The average commute distance grew from 4km in 1957 to 23km in 1975. You'd have to be bike-bonkers to undertake a 25km commute every day, so cars must have been part of this equation (although the Netherlands, in contrast to Ireland also has an integrated and functional public transport system). This all came with a cost, however: in 1971 there were 3,300 deaths on Dutch roads, 400 of them younger than 14.
Everybody cycles - young/old; fat/fit; suit/shorts - and nobody wears a helmet. You can cycle holding hands. You can cycle carrying a bed, an umbrella, your kids, or some flowers.
I've spent about a year of my life living in the Netherlands mostly in big cities (Dublin is bigger than Amsterdam, they are none of them "big cities" like New York let alone São Paulo) including Wageningen, Utrecht, Nijmegen, Amsterdam and Rotterdam. Each town is civilised with its little neighborhoods and I just love the streets, they are so neat, so accessible, so fit for multiple purposes . . . so gezellig.