10. Portugal
We are continuing our list of countries with the cleanest air in the world in 2018 with Portugal, that isn’t famous only for great beaches, but also for its several cities that rank very high for air quality. Porto is the city with the cleanest air, so this can be a good destination for your next trip. Basically, the air in Portugal is good — the median concentration of PM2.5 is 9, the death rate is 17 per 100,000 capita, and it has a population of 10,329,506.
Steve Photography/Shutterstock.com
