Watch Underground Worlds

In this episode we explore the tunnels under the City of Exeter in the UK, unknown to almost everyone shopping in the malls above; we visit a marble quarry in Vermont which has been operating, and extracting marble from under this hillside, for more than a century; and we travel to Moldova, a form Soviet state, now making a name for itself on the world wine stage.

In this episode we explore the subterranean fortifications that have kept Cork Harbour, in Ireland, safe for more than 400 years; we visit a former mineral mine under New Jersey whose walls suddenly and unexpectedly began to deliver a breath taking light show.

In this episode we explore the underground world, rich in history, hidden beneath the picturesque city of Orvieto in Italy; we visit a former limestone mine under Kansas City that has now been converted into a sprawling business complex; and we visit the caves that once offered safe haven for thieves and robbers in the Peak District of the UK.

In this episode we travel deep into an abandoned tin mine, and hear from the new owner about plans to drain the mine shafts and restart production; we visit former Atlas ICBM missile siloes, including one which has been turned into a state of the art survival bunker, ready to weather a modern day nuclear war.

In this episode we head a mile underground in a former gold mine in South Dakota, now turned into a world leading scientific laboratory investigating neutrinos; we visit a huge network of limestone tunnels under a quiet London suburb and hear how it played a crucial role the subterfuge that protected the D-Day landings.

In this episode we explore the vast 400 mile Mammoth Cave in Kansas; we travel into the darkness of the abandoned tunnels of a former Cold War airbase in Croatia; and we crawl through the newly constructed narrow opening into a metal mine that has remained untouched and inaccessible in the mountains of Wales for more than 70 years.

In this episode we explore the top secret, Cold War US government bunker hidden beneath the Greenbrier Hotel in Virginia; we delve into the dark depths of a former slate mine in Wales, UK, to see how the shafts and drifts have been brought back to life.

In this episode we explore the extensive air raid tunnels hidden under the town of Ramsgate in the UK; we head to Butte Montana to see how the former thriving mining town has repurposed the 10,000 miles of tunnels below; and we dive into the Gjovik Cavern Hall, a huge free-standing, ice hockey arena dug under a mountain.

In this episode we explore the Grand Canyon Caverns, North America's largest dry cave system; we visit Cold War radar bunkers around the UK; and we travel to far eastern Europe to the cave city of Vardzia in Georgia, and see the wounds left by 800 years.

In this episode we explore the forgotten underworld of beer brewing tunnels hiding beneath the streets of Cincinnati; we visit a state of the art Cold War fortress on the shores of Denmark, designed to keep the Russian Baltic fleet at bay; and we dive into the historic automobile tunnels guiding cars under the Mersey River in Liverpool since 1934.