Europe

https://archive.is/29uTN

Airparif, an independent group that tracks air quality for France’s capital region, said this week that levels of fine particulate matter (PM 2.5) have decreased 55 percent since 2005, while nitrogen dioxide levels have fallen 50 percent. It attributed this to “regulations and public policies,” including steps to limit traffic and ban the most polluting vehicles.

This would make for such a pleasant city. My downtown core is purely car-centric and it's terrible to visit. Everything smells like exhaust, people are honking and yelling at each other, it's tedious and dangerous to cross the congested streets, and our air quality is terrible to the point of being unsafe for pets and vulnerable groups. Even the plants look like shit because they're so polluted.