These 5 mysterious underground cities were built thousands of years ago — without modern tools, yet with incredible ...

It is the largest excavated underground city in the world and stretches more than 85 metres below the surface.

For most organisms on Earth, rocks are objects, not food. But for one oddball microbe, desert limestone seems to have been on ...

Researchers explore the possibility of a secret passage that may have been used in ancient times for strategic, diplomatic, or commercial purposes.

Researchers mapping a bubble of superheated gas that surrounds our solar system found a surprise, there is a tunnel that may ...

The tunnel under the Temple of the Sun had been ... which held known associations with the supernatural among ancient Mesoamericans, provide further evidence that the buried sub-chambers represent ...

From ancient tunnels to modern memorials, a week in the Holy Land offers a powerful blend of prayer, discovery and awe. Clockwise from left: A view of the Jerusalem model, showcasing how the city ...

If a primordial black hole slices through one of these, it might leave a narrow tunnel in its wake. These tiny paths, no ...

Scientists Found Evidence of Unknown Life in Rocks (Constantine Johnny/Getty Images) 32,256 people played the daily Crossword recently. Can you solve it faster than others?32,256 people played the ...