<strong>West Highland Railway, Scotland: </strong>Offering the "greatest hits" of Scotland's best landscapes, this beautiful line runs 120 miles from Glasgow to Fort William at the foot of Ben Nevis -- the UK's highest mountain -- and delivers a parade of lochs and glens, desolate moors and brooding mountains.
West Highland Railway, Scotland: Offering the "greatest hits" of Scotland's best landscapes, this beautiful line runs 120 miles from Glasgow to Fort William at the foot of Ben Nevis -- the UK's highest mountain -- and delivers a parade of lochs and glens, desolate moors and brooding mountains.
Lukas/Adobe Stock
<strong>Trans-Iranian Railway, Iran: </strong>One of the most spectacular feats of modern engineering, the Trans-Iranian Railway<strong> n</strong>egotiates two formidable mountain ranges with audacious bridges spanning isolated valleys and spiral tunnels that twist locomotives up and down steep gradients.
Trans-Iranian Railway, Iran: One of the most spectacular feats of modern engineering, the Trans-Iranian Railway negotiates two formidable mountain ranges with audacious bridges spanning isolated valleys and spiral tunnels that twist locomotives up and down steep gradients.
Thomas Schulze/picture-alliance/dpa/AP
<strong>The Ghan, Australia: </strong>This epic 1,851-mile route across the parched Australian Outback links Adelaide in the south to Darwin in the north, a trip taking more than 53 hours.
The Ghan, Australia: This epic 1,851-mile route across the parched Australian Outback links Adelaide in the south to Darwin in the north, a trip taking more than 53 hours.
bennymarty/Adobe Stock
<strong>Qinghai-Tibet Railway, China:</strong> Known as the "Railway to Heaven," the 1,215-mile route from Xining to Lhasa tops out at the Tanggula Pass, 16,627 feet above sea level and uses pressurized carriages to minimize the affects of altitude on passengers.
Qinghai-Tibet Railway, China: Known as the "Railway to Heaven," the 1,215-mile route from Xining to Lhasa tops out at the Tanggula Pass, 16,627 feet above sea level and uses pressurized carriages to minimize the affects of altitude on passengers.
Sino Images/500px Asia/Getty Images
<strong>Darjeeling Himalayan Railway, India:</strong> Nicknamed "<a href="index.php?page=&url=https%3A%2F%2Fwww.cnn.com%2Ftravel%2Farticle%2Funesco-kalka-shimla-toy-train%2Findex.html" target="_blank">The Toy Train</a>," the relic of the British empire climbs 7,000 feet over a tortuous 55-mile route between New Jalpaiguri and the hill station of Darjeeling.
Darjeeling Himalayan Railway, India: Nicknamed "The Toy Train," the relic of the British empire climbs 7,000 feet over a tortuous 55-mile route between New Jalpaiguri and the hill station of Darjeeling.
Emad aljumah/Moment Unreleased RF/Getty Images
<strong>Oslo-Bergen Railway, Norway: </strong>This 308-mile trip links Norway's two largest cities -- the capital Oslo, and the west coast port of Bergen. The line, completed in 1909, crosses Europe's largest high mountain plateau -- the Hardangervidda.
Oslo-Bergen Railway, Norway: This 308-mile trip links Norway's two largest cities -- the capital Oslo, and the west coast port of Bergen. The line, completed in 1909, crosses Europe's largest high mountain plateau -- the Hardangervidda.
MariusLtu/iStockphoto/Getty Images
<strong>Bernina Express, Switzerland: </strong>Over river deep and mountain high, this spectacular rail journey traverses the watershed where melting snow can run away to the North Sea, the Mediterranean or even the Black Sea. It's the highest rail crossing in the Alps.
Bernina Express, Switzerland: Over river deep and mountain high, this spectacular rail journey traverses the watershed where melting snow can run away to the North Sea, the Mediterranean or even the Black Sea. It's the highest rail crossing in the Alps.
Sandro/Adobe Stock
<strong>The Canadian, Canada: </strong>Possibly the best way to experience Canada's widescreen landscapes, this rail voyage takes four days to complete 2,775 miles between Toronto and Vancouver, passing forests, lakes and seemingly endless prairies. plus the spectacular Rockies.
The Canadian, Canada: Possibly the best way to experience Canada's widescreen landscapes, this rail voyage takes four days to complete 2,775 miles between Toronto and Vancouver, passing forests, lakes and seemingly endless prairies. plus the spectacular Rockies.
Via Rail
<strong>The Little Yellow Train, France: </strong>Hugging the sides of the deep, rocky valley of the River Tet in the Pyrenees mountains, the line winds between forests, chasms and gushing streams, passing traditional villages, historic fortresses and a precariously perched hermitage.
The Little Yellow Train, France: Hugging the sides of the deep, rocky valley of the River Tet in the Pyrenees mountains, the line winds between forests, chasms and gushing streams, passing traditional villages, historic fortresses and a precariously perched hermitage.
Matteo Scarano/Adobe Stock
<strong>The TranzAlpine, New Zealand: T</strong>he TranzAlpine takes four and a half hours to cover just 139 miles, but packs in diverse landscapes ranging from the Canterbury Plains to the snow-capped mountains of the Southern Alps, remote alpine meadows and the lakes, streams and forests of the island's West Coast.
The TranzAlpine, New Zealand: The TranzAlpine takes four and a half hours to cover just 139 miles, but packs in diverse landscapes ranging from the Canterbury Plains to the snow-capped mountains of the Southern Alps, remote alpine meadows and the lakes, streams and forests of the island's West Coast.
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