"Oulu is notable for its transportation network dedicated to non-motor vehicular traffic, including pedestrians and bicycles (termed "light" traffic in Finland). In 2010, the city contained more than 600 kilometres (370 mi) of pathways and more than 100 underpasses and bridges devoted exclusively to light traffic. The network is used year-round. The ratio of light traffic pathways to residents is the highest in Finland and the cycling mode share is 20 percent.[40][41] Oulu is often touted as an excellent city for bicycling."
Many cities have roads and bridges only devoted to light traffic, the real issue is that they are not excellent for biking. In many large cities the biggest problem is distances.
Sub zero temperatures are an issue even for professional bikers at Tour de France.
When the road conditions are not uniform and distances are longer than a few minutes ride they can cause serious problems.
For example imagine going uphill and then down, exposed to the chilling weather and the consequences on a casual bike user.
https://en.m.wikipedia.org/wiki/Oulu
"Oulu is notable for its transportation network dedicated to non-motor vehicular traffic, including pedestrians and bicycles (termed "light" traffic in Finland). In 2010, the city contained more than 600 kilometres (370 mi) of pathways and more than 100 underpasses and bridges devoted exclusively to light traffic. The network is used year-round. The ratio of light traffic pathways to residents is the highest in Finland and the cycling mode share is 20 percent.[40][41] Oulu is often touted as an excellent city for bicycling."