Seeing inside secret hidden Tunnels underneath our French Chateau (what did we find!)

The Secret Military Fortresses Hidden in the Swiss Alps

The Sussex secret tunnels that lay hidden beneath our feet - SussexLive

Castle built atop a Fortress - Château de Brézé - Bellevigne-les-Châteaux, France - Beneath its foundation lies one of Europe's largest underground fortress - Connected by more than 3 kms of tunnels

Castle built atop a Fortress - Château de Brézé - Bellevigne-les-Châteaux, France - Beneath its foundation lies one of Europe's largest underground fortress - Connected by more than 3 kms of tunnels

Notes From the Underground: The Long History of Tunnel Warfare

Escape to the 800 year old Chateau du Masgelier in France - The Good Life France

Knights Templar unmasked: Underground tunnels found at society's 'Vatican' stronghold, World, News

The Kent secret underground tunnels totally hidden beneath our feet - Kent Live

The Ultimate Guide to Paris Underground (by Locals!)

Virtual 'tunnel tours' show secrets of Fenland town hidden underground

We Found Hidden Tunnels underneath our French Chateau

Another dream of mine is to go in any underground tunnel!

This family bought a French château with secret tunnel for £370k