Think the world is your oyster? Think again! From top secret HQ’s to secretive underground train networks – we run through the Top 12 places you won’t be entering anytime soon for love nor money.
Lascaux Caves – France
Found in South West France, Lascaux is complex of caves that are world-renowned for its Palaeolithic cave paintings that are estimated to be over 17,500 years old. Although these caves were once open to the public, they have since been closed to preserve the original artwork.