Once a sewer culvert, this road tunnel now offers cyclists and pedestrians a subterranean stroll under the C&O Canal.

Unusual building appears to be haphazardly built from randomly piled bricks.

The last standing example of an ancient district's teatime tradition.

When the Soviets destroyed the historic Armenian monastery they somehow left its bell tower intact.

With over 10,000 lights, this engineering marvel lights up the city after dark.

Get in line for Lisbon’s most famous sandwich.

Sip cherry liqueur at a bar dating back to 1840.

Eat the ultimate iteration of Portugal's most beloved pastry.

One Portuguese poet described this cape, the westernmost point in mainland Europe, as "where the land ends and the sea begins."

Men in rubber-soled boots serve as your "brakes" on this toboggan ride Hemingway described as "exhilarating."

At night, bats patrol this magnificent 18th-century space in search of book-eating pests.

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

This once-forgotten oasis in the middle of Lisbon was first created over a century ago quite by accident.

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

A king's pet, a pope's gift, an artist's inspiration, and a tragic shipwreck.

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

This charming candle shop has been in business since 1789.

This small chapel is built of human bones and decorated with a golden skeleton.

One of the world's largest model railroads is a mind-boggling achievement.

A former barn converted into a massive train diorama.

This delightful attraction features over a dozen miniature train layouts which you can operate and interact with.

A Jenga-style cylindrical tower of books that appears to go on forever.

Once the foundation for a mansion, these ruins now offer amazing panoramic coastal views.

This neon blue river gets its color from a unique mix of bacteria and volcano minerals.