The title of "scariest train" is often given to the Tren a las Nubes (Train to the Clouds) in Argentina, due to its extreme altitude and breathtaking engineering. This rail journey climbs to over 4,200 meters (13,800 feet) above sea level in the Andes Mountains, crossing the massive Polvorilla Viaduct, which is 63 meters high and 224 meters long. What makes it "scary" for many is the sheer drop-offs and the fact that the train often appears to be floating in mid-air above the clouds with no visible support from the windows. Another contender is the Pilatus Railway in Switzerland, which is the steepest cogwheel railway in the world with a terrifying 48% gradient, making passengers feel as if they are ascending a vertical wall. For those who fear heights and narrow passages, the Pamban Bridge train in India is equally nerve-wracking; the tracks sit just a few meters above the crashing waves of the Indian Ocean on a century-old bridge that often sways during monsoon winds. While all these trains are exceptionally safe and meticulously maintained, the combination of high-altitude exposure, extreme inclines, and the visual sensation of being suspended over deep gorges or open oceans creates a visceral sense of fear for many travelers.