As you mentioned, electric bicycles flatten terrains (so do wide gear ranges), and jackets neutralize climate. There seriously isn't anywhere that is inappropriate to cycle. The only major limiting factor for people feeling comfortable biking everywhere is the threat of violence due to people driving cars.
replyLightening is another limit. I'm going to drive to work today because there is a 20% chance of thunderstorm when I'm planning to going home, and that is too much risk.
replyWithout studded tires it’s very difficult to ride a bike on snow or ice.
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