Exploring the forgotten underworld hiding beneath the streets of Cincinnati, USA. Plus, a state-of-the-art Cold War fortress on the shores of Denmark.
All episodes for series 2 of Underground Worlds
S2 E2 · Grand Canyon's Lost Treasure
Exploring inside the Grand Canyon Caverns - North America's largest dry cave system.
S2 E3 · Cincinnati's Secret Caverns
Exploring the forgotten underworld hiding beneath the streets of Cincinnati, USA.
S2 E4 · Hotel Bunker of the Apocalypse
Exploring the secret, Cold War US government bunker hidden under Greenbrier Hotel in West Virginia.
S2 E6 · Ireland's Underground Alcatraz
Exploring hidden defences that have kept Cork Harbour, in Ireland, safe for many years.
S2 E7 · Medieval Maze of Secrets
Exploring tunnels beneath Exeter that were built in medieval times to protect the city.
S2 E8 · Buried Lab of the Black Hills
Exploring a former gold mine turned scientific laboratory in South Dakota.
S2 E9 · Subterranean Silo Survival
Exploring old tunnels in an abandoned tin mine beneath the moors of Cornwall.
S2 E10 · Italy's Subterranean Secret
Exploring the caves beneath the beautiful city of Orvieto in Italy.
The Architecture the Railways Built
Description: Tim Dunn explores the stunning architecture that lines the railway network.; Category: Engineering; 40 episodes available.
The Buildings That Fought Hitler
Description: This series looks at just some of the buildings that were designed to fight Hitler.; Category: Military & War; 8 episodes available.
Guy Martin's World War 1 Tank
Description: Guy builds a working replica of a WWI tank and drives it at a Remembrance Day parade.; Category: Factual Entertainment; 1 episode available.
Guy Martin's Lancaster Bomber
Description: The history enthusiast honours Lancaster bomber crews of the Second World War.; Category: Military & War; 1 episode available.
How Britain Worked
Description: Guy Martin recreates technical achievements of the 19th century.; Category: Engineering; 6 episodes available.
Guy Martin's Spitfire
Description: Guy joins the two-year restoration of a Spitfire that was buried in a French beach.; Category: Engineering; 1 episode available.
Britain's Ancient Capital: Secrets of Orkney
Description: An investigation into Orkney being the capital of Stone Age Britain.; Category: History; 3 episodes available.
David Jason's Secret Service
Description: David Jason offers insights into modern British spy history.; Category: History; 3 episodes available.
England's Forgotten Queen: The Life & Death of Lady Jane Grey
Description: The story of the de facto Queen of England and Ireland for nine days in 1553.; Category: History; 3 episodes available.
American History's Biggest Fibs
Description: Lucy Worsley explores how American has been mythologised and manipulated.; Category: History; 3 episodes available.
