SubTropolis Missouri: The World's Largest Underground City

Added: 2026-05-17

[00:00:00]Deep under Kansas City, Missouri, thousands of people drive to work inside a giant rock. This is SubTropolis, the largest underground city in the world.

[00:00:08]It started as a huge limestone mine.

[00:00:10]Today, it is a massive business complex.

[00:00:12]This unique architecture is totally hidden from the sun. Down there, the weather never changes. It stays exactly 68° every single day. Because this engineering marvel is so safe, it is perfect for secure storage. Companies hide their most prized items inside the rock. It holds priceless movie tapes, old papers, and even giant caves full of cheese. America has a secret world right under our feet. It is bigger than 42 football fields. This hidden city is so huge, it has its own paved roads, stop lights, and street signs. You could run a business down there right now and never see a single drop of rain.