The Massive Steam Pipes Beneath Manhattan

New York City hides the world's largest steam system under its streets. Since 1882, this hidden network has pumped hot steam to heat and cool skyscrapers and disinfect buildings across Manhattan.

While most cities rely on electricity or gas, parts of New York are still powered by 19th-century infrastructure technology on a massive scale. The steam system carries high-pressure vapor through underground pipes to power heating and cooling for famous landmarks and universities. It serves as a living piece of history that remains essential to the city's daily operations. Even today, it remains the largest district steam system globally.