Americans living in big cities like New York or Los Angeles are familiar with the stress of overcrowded streets and sidewalks and the lack of parking. It’s nearly impossible to find a spot to spread your beach blanket at Coney Island in the summer, and the long wait to cross the George Washington bridge connecting Manhattan with the borough of Fort Lee in New Jersey should be a crime.

But take a look at the crowds from another perspective: In the United States, we don’t actually  know anything about real overcrowding — not a single American city ranks among the top 50 most densely populated urban areas in the world. At the other end of the spectrum, these are the least densely populated places in the world. 

A variety of factors help explain the high density of these cities, where it seems impossible to walk without bumping into pedestrians every second: more births than deaths, people moving to cities for jobs or forced off rural land by natural disasters, skyrocketing land prices, to name a few. 

Population density is determined by the number of residents who live within a given land area — usually a mile or kilometer. According to the United Nations, as of 2016, about 55% of the world’s population lives in urban areas. This is expected to grow to 60% by 2030, with one in three people living in cosmopolises with at least 500,000 residents —  maybe in some of the world’s 33 megacities. 

In time for the World Population Day, marked every year on July 11 to raise awareness about urgent population issues, 24/7 Tempo identified the most densely populated cities in the world, using data from CityMayors Statistics, a global source for urban statistics. 

Click here to read about the 50 most densely populated cities in the world.