Perhaps the most spectacular grotto along the Algarve coastline.

The oldest candy store in the world has been selling traditional sweets since 1827.

This museum inside a museum tells the story of London's timepieces.

Below a historic English market town lies a secret underground city complete with kitchens, laundries, storerooms, and an underground lake.

This hunter-gatherer architecture is believed to be the oldest religious complex known.

Hundreds of prehistoric stones, arranged in perfect lines in a French field.

World's largest Christmas store.

These tombs were built into the side of a mountain so that ancient angels could reach the dead.

One man single-handedly dug a road right through a mountain after his wife died due to its interference.

Angels, demons, and tortured souls on a giant wall mural in a little church.

A 10 million-ton rock once worshiped by the Tahamies Indians, accessed by an astounding staircase.

It seems that the residents of of this megalopolis suddenly vanished, but they were never actually there.

Small church on top of a huge rock column.

These Stalin-era industrial 'death traps' hang lifeless above the city

Yugoslavia's biggest underground airport lies in ruins.

A small church ornamented with medieval erotic sculptures.

The sign at the garden gate reads: "These Plants Can Kill."

The industrial monstrosity known as Bagger 258 is a colossal mining machine built in the DDR - but now left for dead in a German field.

This historic timepiece is thought to be the only public clock in the world that keeps lunar time.

The largest preserved walking dragline excavator in Western Europe.

A museum devoted to the science of color.

This Tang Dynasty behemoth is the biggest Buddha in the world.

Over 2,000 ancient temples dot the Myanmar landscape at the site of this famed archaeological site.

Catalonia Tradition: Beating the hollow Christmas log until it defecates in your fireplace.