In my city (Tampere, Finland, pop. ~260,000) the annual number of traffic accidents leading to injury has halved since 2010. A big driver has been the decision in 2015 to lower the speed limits on all local streets from 40km/h (25 mi/h) to 30 km/h (~20 mi/h), with appropriate traffic calming measures implemented where necessary. (Industrial zones are exempt.)

A map link showing the current state:

https://kartat.tampere.fi/oskari?zoomLevel=7&coord=327979.56...

That's an area surrounded by a lot of water!

TIL that Nokia originated in Tampere.

Thank you for the information sharing!

A lot of water indeed, and it’s not even considered a part of what’s called the Finnish Lakeland proper! [1]

And yep, Nokia is literally the name of the town it originates from.

[1] https://en.wikipedia.org/wiki/Finnish_Lakeland

I hope the traffic calming measure is the speed display that shows a sad face when you are speeding.

Well, there are a couple of those. But mainly we’re talking about the basic things: narrowing lanes, speed bumps, raised zebra crossings, preventing through traffic, rebuilding intersections as roundabouts and so on. The key points to preventing speeding are

* reducing drivers' perceived safety, and

* making it more uncomfortable for the drivers to speed.