The world is full of wonders, from abandoned towns and deserted settlements to underwater cities and underground architecture. Humans burrow into the Earth out of anything from necessity to superstition, driven by coincidence or coerced by circumstance. Without further ado, here are seven more underground wonders of the world.

What motivates humankind to burrow deep into the Earth? From London to Paris, Budapest to Moscow, the USA to Australia, here are seven of the most amazing examples in the world. Some were built for military defense or shelter, many are abandoned while others thrive. These amazing images feature tunnels, caverns, labyrinths from seven underground location around the world, following the acclaimed
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