Calcium carbonate dust found in the tunnels is also a common excretion from microbes that live in these types of rocks. However, no fossilized organisms have yet been found—just evidence of ...

But below the city's streets is something few people know about - an underground network of tunnels holding the remains of millions. The Paris Catacombs stretch beneath the city and contain the ...

The House of Representatives passed a bill aimed at cracking down on Mexican cartels' use of tunnels underneath the southwestern border to smuggle illegal immigrants and illicit items the U.S. The ...