Elaborately carved to showcase the glorious wealth that the age of exploration brought to the Portuguese empire.

This Industrial Age architectural and engineering gem helps visitors and residents alike traverse Lisbon, “The City of Seven Hills.”

An ancient and majestic fortress that played an integral role in Portugal's road to independence.

This eccentrically decorated palace is replete with grottoes, fountains, tunnels, and caves.

This unreal Portuguese palace looks as though it's made from a pile of different castles.

Thousands of coffin-like pillars make up this controversial Holocaust memorial.

The most visited, and possibly most controversial, museum in Germany.

There must be a pun in this haystack somewhere...

The most confusing clock in New York.

A curious fountain that has no water and includes Satan, a crab, and 9 giraffes.

Mysterious 500-year-old tapestries depict a unicorn hunt.

A three-story copper skybridge connects two Manhattan buildings with Art Deco luxury.

The feral felines of Roosevelt Island have a small army of allies and an abandoned hospital all to themselves.

Elevated freight railway turned wildly successful urban park.

A crumbling hospital from the 1850s on Roosevelt Island.

A terrific purveyor of natural history objects and curios.

Meet the bronze beloved pet to a family of famous peeing statues.

This collection of over 50 murals celebrates Brussels' rich history as the self-proclaimed home of the "comic strip."

A little sculpture with a large wardrobe.

Climb inside an iron crystal magnified 165 billion times its normal size.

Iconic rock formations that allow for exploration during high or low tide.

The biggest museum dedicated to insects in North America, one of the largest in the world.

This three-chambered cave is the only protected natural bat hibernaculum in Quebec.

Dramatic river bend surrounds a natural red-rocked pedestal.