Public transportation is a quick and easy way to navigate through a major city. Thankfully, this type of mass rapid transit is also quite affordable, but you’ll likely be packed inside a tiny subway car if you use the metro in any of the cities on our list. Here’s a look at the busiest underground rail systems in the world based on the average daily and annual ridership.
1. Beijing Subway, China
Known as one of the cities with the worst traffic, Beijing residents have discovered the best way to get around this bustling city is on its busy subway system. Sure, residents are packed like sardines inside the tiny cars, but it’s better than being stuck on the city’s 50-lane freeway for hours on end!
The subway opened on Oct. 1, 1969, and its 22 lines and 370 stations averaged 3.66 billion trips in 2016.