Crystal clear lake with a shoreline of travertine located in a Colorado canyon.

The world's largest drain sits below the city of Kasukabe, Japan.

A glacier pocked with ice caves and surrounded by rainforests.

The gorgeous library at Trinity College is home to remarkable treasures of Irish identity.

Each spring, a dreamlike carpet of bluebells overtakes the forest floor.

A striking 12th-century-style castle built on the edge of a cliff.

Started as a kitchen garden, now the second largest botanical garden in the world.

The fairy tale castle of the "fairy-tale king."

Snow-capped peaks, colorful waterfalls and stunning vistas on the edge of the Himalayas.

A complex and beautiful system of rice terraces covers a million acres over the mountains.

For those with no fear of heights: a skywalk 4,700 feet up on a Chinese mountain.

A part of the world's largest marsh seems to be growing bright red Martian grass.

These layered sandstone mountains in China look like they are made of pressed crayons.

Intensely colorful calcite pools in Southern China.

This abandoned fishing settlement may well be the greenest village in the world.

This vertical pinnacle in China was the inspiration for the floating mountains in the movie “Avatar.”

The 43-mile route crosses through six islands with gorgeous views of the Seto Inland Sea.

An abandoned Art Deco hotel nestled on the side of a wooded mountain.

Perhaps the world's cheapest vending machines.

A miniature rainforest is growing inside of a Midtown Manhattan office building.

This dramatic landscape hidden on the Isle of Skye looks as though you've stepped into the magical realm.

This jaw-dropping 19th-century bridge uses its reflection to form what appears to be a perfect circle.

France's most famous cemetery, with some of its most curious tombs.

Over 40 species of fern cover the canyon walls of this lush green bowl, cut off from the bustle of the world by a cave entrance.