Where the sleeping monsters of Scotland's oil industry are left to rust.

This astonishingly geometric cave has inspired everyone from Jules Verne to Pink Floyd.

A red sandstone freestanding monolith rises out of the sea in northern Scotland.

Amazing and mysterious Neolithic settlement on Scotland's Orkney Islands.

This tiny island featuring 9th-century Viking ruins is only accessible at low tide.

The true age of this ancient stone circle is unknown, but its stunning vista isn't in question.

The ruins of an abandoned crematorium haunt an eerie deserted German cemetery.

Retirement home for giant obsolete machines.

This beach runway is off limits during high tide.

The last inhabitants of one of the U.K.'s most remote islands were evacuated in 1930.

Barcelona's historic 19th-century sewers, whose foundations were laid in medieval times, are open to the public for exploring.

This natural Icelandic fissure allows divers to swim right between two volatile tectonic plates.

This volcanic cave lake is essentially hard proof that Iceland is the most magical place on Earth.

The world's most delightful not-NOT-religion welcomes visitors to the town of Templin, just like its more stoic peers.

A tiny island is connected to the mainland by a private railway that residents travel in their own personal wagons.

This fantastical waterfall is hidden in a cave located in a cracked cliff.

This semi-secret storybook hedge maze is also the oldest garden in the city.

Hamburgers are intensely proud of their tunnel beneath the river.

Once the tallest building in the world, this abandoned church is now a monument to the destruction of WWII.

An unusual stroll through gentlemen's erotica demonstrates that pornography is timeless.

Remnants of an exploded schooner and wrecked submarines form a breakwater.

The world's first zoo for microbes collecting the horrible and wonderful things living on and around us.

A fascinating little museum dedicated to the thousands of chemical substances concealed in our food.

Model Trains and Much More in Hamburg.