Underground Worlds

Sep 25, 2019 · 45m

This edition explores the hidden network of tunnels and caves beneath Gibraltar that were instrumental to the Allies success during WWII. Plus, the ultimate super-sewer beneath London and a breathtaking cave system in Postojna, Slovenia.

Oct 2, 2019 · 45m

Explores how Sweden has gone to extraordinary lengths to protect itself - by excavating 65,000 nuclear bunkers. Plus, Somerset's Cheddar Gorge and an underground first in Romania.

Oct 9, 2019 · 45m

A look at some of Switzerland's 300,000 subterranean bunkers, the creation of a local entrepreneur shrouded in mystery in England and a network of tunnels deep beneath Slovenia.

Oct 16, 2019 · 45m

The Wieliczka Salt mine in Poland, some 327 meters deep, where the voids left behind from excavating salt have been transformed into extraordinary spaces, carved by hand.

Oct 23, 2019 · 45m

A labyrinth of tunnels underneath a tiny French village which contains mysteries from several historical eras, and a Welsh slate mine that has been given a new lease of life.

Oct 30, 2019 · 45m

An underground city beneath a forest in Northern France built to house 3,000 people, an ice cave under Iceland's biggest glacier, and a subterranean power station in London.

Nov 6, 2019 · 45m

The underground bases built by the German army during the occupation of Jersey, and a group of more than 20 underground cities in Turkey, one of which dates back to 800BC.

Nov 13, 2019 · 45m

The secrets of the largest subterranean fortress along France's border with Germany, and a look at how a unique precious mineral was discovered in Derbyshire.

Nov 20, 2019 · 45m

The sinister history of Edinburgh's vaults and the development of Helsinki's subterranean spaces. Plus, the impact of the building of Naples on the volcanic ground below.

Nov 27, 2019 · 45m

This edition explores the military headquarters built beneath Dover Castle during the Second World War, and Odessa's catacombs, possibly the largest tunnel network in the world.