Stenciled handprints and wall paintings dating back 10,000 years, some of the earliest forms of cave art.

A quiet memorial to those who died saving others in the heart of the City of London.

The former home of a mad diplomat is said to still be marked in bloody, arcane scrawls.

Cat art as far as the eye can see.

Outdoor art exhibition made of classic Tetris pieces.

This secret Australian garden was built on love after a man planted a random bulb he found in the ocean.

This churchyard arbor is surrounded by hundreds of gravestones placed there by author Thomas Hardy.

This artist's home turned gallery/museum preserves the creator's love of "Eastern" influences.

A memorial to a dog that inspired rioting in the streets of London.

There is a mouldering Jewish cemetery hidden away in the capital of Moldova.

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

999 stairs lead visitors through a massive hole in a mountain known as the Gateway to Heaven.

These mammoth-yet-narrow crevasses in the Earth are perfect for taking an otherworldly swim.

The most alien-looking place on Earth.

Skyscraper powered by wind turbines attached between its towers.

The small cliffside monastery known as the Tiger's Nest is said to be the meditation site of an eighth-century Buddhist master.

One of the largest Buddhist stupas in the world keeps an eye out in every direction.

One man's labor of love, Amman's oldest home has become a time capsule with its doors permanently open to artists and guests.

Ancient Manuscripts showcase the civilization of West Africans during the Middle Ages.

The largest stone moai on Rapa Nui.

A musical instrument played by the sea.

Budapest's Communist-era statues, banished to the suburbs.

A fake Transylvanian castle houses a cathedral of antlers.

A 19th century artistocrat's mansion, turned into a library, hidden in a modern library.