[eythian]

> Why do adults cycle so slowly there though? 12km/h is a moderate running pace.

A couple of reasons. One is that it's a nice pace for getting to where you want to go without being all sweaty when you get there. Another is that the bikes are built for practicality, not performance. As such, they're cheap (so when they get stolen, it's annoying but not the end of the world), they often are single speed with coaster brakes (less to go wrong), heavy (so built solid), and comfortable (mine is like riding a couch.) You're also often biking with a swarm of other people and so just keeping the common pace is nicer.

I find that my average Amsterdam speed is about 15kph, and that's probably slightly above average, based on anecdotally passing more people than pass me.

If you're cruising on a non-electric bike at 30-35kph you're probably a lot fitter than is typical, or showing up a bit sweaty and worn out. On my 3-speed Gazelle that is very heavy but can also carry two people and a case or two of beer (though I did find the limit of that, so long as combined we're under about 170kg or so it's OK), I really only use the 3rd gear to do a fast burst probably up to 20-25kph in "oh no the ferry leaves in 3 minutes but it's normally a 5 minute ride" situations. But I feel it when I get there.