We often wonder what ancient cities looked like, what buildings, walls, and colors did they feature. But rarely do we ask: ...

The world’s largest underground floodwater protection system, a colossal underground flood tank aimed to shield Tokyo from ...

depending on how the city was set up. Here are a few of the most prominent ancient underground cities in the world. The Cappadocia region of Turkey is abundant in underground settlements and cliffside ...

Eversource, a New England-based energy provider, broke ground in Kendall Square on Tuesday on what will be the largest ... underground, will provide enough energy to replace 50 percent of the city ...

Through a basement door in southeastern Turkey lies a sprawling underground city — perhaps the country's largest — which one historian believes dates back to the ninth century before Jesus Christ.

Because more than half of the city’s water supply comes from underground aquifers ... Latin America’s oldest — and one of its largest. Walking from chamber to chamber, tourists snapped ...

Prior to this discovery, the largest underground thermal lake title belonged to a site in Hungary, below Turkish baths in the city of Budapest, Reuters reported in 2008. That lake is 282 feet long ...