Here’s a good example of why multi-use paths don’t work. I took this photo in Frankfurt last spring. This asphalt path runs along the river Main, stretching out from the city center through some lovely wooded land. I’d guess most use is recreational but people do commute on it. It’s wide by American standards, plenty of room for two-way cycling traffic, but it fails because it’s multi-use. It doesn’t delineate between pedestrians and cyclists and so even with all that asphalt, people have carved out this dirt rut to one side. That’s where the runners go when the cyclists come in both directions or where the cyclists go to get around strolling pedestrians.

Why do we build paths like this? It’s clearly not a space issue and it’s clearly not working for its users—they’ve gone and trod out the separation they need. I don’t have any idea how well it works in Germany, but on paths like this here the mixing only encourages conflict. I see it all the time on our rails-to-trails paths, pedestrians and cyclists yelling at each other, playing chicken—our state paths mandate pedestrians walk against on-coming cycling traffic, so this chicken game happens at nearly every interaction. Paths are supposed to be the place cyclists go to get away from the dangers of road traffic, places of high subjective safety. But when pedestrians aren’t separate those same dangers are present, they just move a lot more slowly.