It varies from day to day, but people burn coal in their homes to stay warm and it can become really difficult to breathe. Prishtina is consistently the most air-polluted city in Europe. One day last month, we were the most air-polluted city in the entire world. The air clears up as the weather gets warmer, but it's a definite downside to living here. It makes me feel really grateful for the clean air we have back home.