World's Most Dangerous Railways

In northern Argentina, the Tren a las Nubes or the cloud train, crosses dizzying viaducts and deep valleys; at an altitude of over 4000 meters, what was once the highest railway, runs past cactus forests and into the driest desert in the world.

The story of the world's most unusual and dangerous railways.

The Pamban Railway crosses the tropical landscape of Tamil Nadu, the former Madras, for around 600 kilometers.