World cities turn their streets over to walkers and cyclists Lees het hier :World cities turn their streets over to walkers and cyclists The Guardian, 2020-04-11https://www.theguardian.com/world/2020/apr/11/world-cities-turn-their-st... Lees verder →11/04/20Tags: traffic nitrogen dioxide levels Air pollution COVID-19 Corona lockdown reallocating road space socially distancing