Château de Brézé isn't just a castle – it's a medieval survival masterpiece hiding 3 kilometers of underground tunnels, rooms, and an entire troglodyte city carved into limestone. While most châteaux had cellars, Brézé went full underground with bakeries, stables, silk farms, and escape routes dating back to the 11th century. French Château Hides an Underground City - 3km of Secret Tunnels | Château de Brézé | 12:07 Saving Castles | 27.4K subscribers | 3,143 views | July 13, 2025 Chapters: 00:00 - The Castle With a Secret 02:30 - Inside the Grand Salons 05:45 - Descending Into the Underground...