One of the most interesting experiences in my life was visiting Tel Aviv on Yom Kippur. On that day all car traffic is prohibited (also TV stations are offline etc). It was absolutely amazing. Tel Aviv is a city with large roads and usually extremely busy. On that day, cyclists ride over the highway, kids play on the streets. I never felt that directly before how invasive the normal car situation is.
Here's a photo https://static.timesofisrael.com/www/uploads/2015/09/F141003...