Places Mike Walker Wants to Go

The longest navigable underground river in the United States is home to countless blind and albino animals.

A hidden network of subterranean passageways lies tangled beneath Indianapolis' bustling City Market.

One of Antoni Gaudí's most classic buildings is well-known for its "dragon-back" design.

This hidden courtyard in the Andorran capital hosts a unique contemporary sculpture park.

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

Perhaps the most spectacular grotto along the Algarve coastline.

"Portugal's Stonehenge" is made up of nut-like stones aligned with the heavens.

A 16th century chapel decorated with bones, skulls, and entire bodies hanging from the wall.

Get in line for Lisbon’s most famous sandwich.

One of the smallest bookstores on the planet.

Legacy of the earthquake that nearly wiped Lisbon off the face of the Earth.

This charming candle shop has been in business since 1789.

This little-known national museum houses over 40,000 works of art from across the world.

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

One man's remarkable private collection of art from around the world.

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

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

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

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

The verdant mossy ruins of a Franciscan monastery lie in the remote Sintra hills awaiting exploration.

A unique seaside cave where Aleister Crowley faked his own death.

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

In Portugal, a secluded stretch of untouched natural beauty hides at the bottom of a steep hill.

This enigmatic Roman tower lurks just outside Belmonte.