In 2008, Gaspar Duval was a 46-year-old amateur photographer with a passion, taking pictures

of off-limits hard to reach places in Paris like rooftops or abandoned railways.

One day, as he was walking through an abandoned tunnel, he noticed a strange hole in the ground.

He decided to climb in.

I had passed my head in the hole and I saw there was a tunnel in three dark and humid shadows.

I went in and I walked in more and more deep tunnels.

I didn't know what it was but I had no desire to go back to explore everything.

Gaspar had stumbled into a secret entrance to one of Paris' most unique landmarks.

The catacombe de Paris, the Paris catacombs, a historic 150-mile long network of tunnels

that spreads like a maze underneath the city.

These tunnels are filled with the bones of millions of Parisians laid to rest centuries ago.

You don't know it, but under Paris, there is another one.

A city under the city, kilometers and miles of tunnels.

The catacombs of Paris tell a story of Paris and even of France's history.

But the most part of this tunnel is forbidden.

A small section of the Paris catacombs is open to the public.

But on that day, Gaspar had entered a section that was off limits and he was mesmerized.

Since that day, 15 years ago, Gaspar has photographed every corner of the Paris catacombs.

And today he is going to show us the catacombs through his lines,

taking us through the elaborate tunnels that reveal Paris' history.

This visit will be a journey in time through the history of catacombs.

This journey will be sometimes dark because we will be confronted with death.

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