Most people exploring a city focus on what’s above ground. But in several cities across the U.S., there's an entirely ...

We discovered a hidden tunnel that runs directly beneath the city – and what we found inside was unreal. In this video, we explore its dark corridors, forgotten chambers, and the eerie silence ...

Ancient city discovered under Wyoming's Horse Peak mountain? The underground city was said to cover several square miles and be more than 12,000 years old.

How can it be that a large lake went undiscovered for so long? Simple, it is underground in a cave system. The cave system is ...

London's Secret Wartime Tunnels Are Set to Draw Tourists with a Spy Museum and Underground Bar A general view of one of the tunnels during a press tour London, Thursday, June 19, 2025.

Republicans are proposing to dramatically roll back tax breaks designed to boost clean energy projects fueled by renewable ...

A long-secret network of tunnels 100 feet below the streets of London could be the city’s next big tourist destination. Local authorities have approved plans to fill the site — originally dug ...

The tunnels lie directly below London Underground’s Central Line in the city’s Holborn area. Work to dig them began in secret in 1940, when Britain feared invasion by Nazi Germany.

The tunnels lie directly below London Underground’s Central Line in the city’s Holborn area. Work to dig them began in secret in 1940, when Britain feared invasion by Nazi Germany.