Underground structure filled with skulls in Paris.

One of the most famous underground structures in the French capital is the Paris Catacombs. It is considered one of the most impressive underground complexes in the world. The Paris Catacombs are part of an ancient network of underground structures that exist beneath Paris and are also known as the 'mines'.

These tunnels originated from limestone quarries, which were exploited during Roman times.

The walls were covered with bones and skulls.

This is the final resting place of hundreds of thousands of Parisians throughout history.

The catacombs are now open to visitors.

A 'mountain' of human bones inside the tomb.

Because there are valuable historical structures here, they are regularly inspected and protected by the authorities.

The sculptures inside the tomb.

The walls of the Paris Catacombs.

Many sculptures, like small churches, are located inside the catacombs.

Human bones were found everywhere.

This is a unique structure, a different side of Paris compared to the splendor above.

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