Watch Secrets of the Railways

Winding its way through the Australian rainforest, a train carries tourists daily on its picturesque journey among ancient trees, towering mountains and majestic waterfalls before reaching the tableland above. But this railway line has a hidden story that links deadly animals, mysterious holes in the ground and WWII's Pacific War.

This unassuming railway line revolutionised how we travelled and propelled mankind into the modern world. But at what cost? Quicksand like bogs needed to be crossed, fears and superstitions surrounded it and, as if it was a self-fulfilling prophecy, tragedy struck on its maiden voyage...

When first constructed, it was the northernmost railway line on earth and today its locomotives are among the most powerful ever built... But its secret story remains hidden at the bottom of a nearby fjord where the wrecks of Nazi destroyers and Allied ships lay testament to the crucial role it played in WWII.

In this episode, we discover how over 100 years ago a remote railroad fought against impossible odds in order to transport the prospectors of the Klondike gold rush. From gangsters and gold miners to Donald Trump's grandfather, this is the story of how a remote railway changed the lives of those who came in search of the American dream.

This historic railway, complete with a vintage steam train making its way through picturesque German villages, and ancient forests of the Harz mountains is the stuff fairy tales are made of. But its past is scarred with haunting secrets. It holds tales of witches, human suffering and a top-secret Nazi weapons programme.

A luxurious station in the Pyrenees mountains that was once the second largest in Europe, now lays abandoned at the border between France and Spain. In its heyday, it was a real-life Casablanca. The railway line that ran through it during WWII set the stage for tales of espionage, Nazi gold and the fight against tyranny.