Ultra-marathoner Thai Richard spent two years documenting his ambitious runs that mirrored the city's transit system.

TV shows. Gambling. Cosmetics. These are just a handful of businesses that advertise with the MTA throughout its massive subway system. Some of the ads are fun, colorful and even – some New Yorkers ...

Global warming is driving dangerous and disruptive flooding in underground rail systems around the world. Flooded tunnels and stations have disrupted service and stranded passengers in Boston, London, ...