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

The medieval castle built as headquarters for the Pope's secretive Knights Templar.

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

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

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

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

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

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

One of the most beautiful bookstores in the world hides a neo-Gothic interior behind an art nouveau facade.

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

Originally used to sell brandy, the bull-shaped billboard became an iconic symbol of Spain.

The iconic boulevard is the perfect place to catch sight of a bicycling skeleton, a levitating Satan, or a chef with his head stuck in a pizza.

This beautifully verdant lagoon is tucked below a massive volcano in a crater atop a black pebble beach.

Spain's unique Mosque-Cathedral has been a place of worship for both Muslims and Christians throughout its history.

A 16th-century Andalusian palace.

A contemporary art installation housed within a Gothic cathedral.

Possibly the oldest church in Barcelona, this basilica has its pagan and Christian mythologies all mixed up.

The 2,000-year-old Roman columns are hidden within Barcelona's Gothic Quarter.

Visit a surreal landscape so otherworldly NASA actually used it to train the Apollo 17 crew.

A vista of the city and sea from atop the little-known viewing deck on an unassuming Columbus statue.

The chefs at El Diablo use heat generated by an active volcano to cook the food.

This former Baroque palace on the historic Calle Montcada is a rare architectural gem and was once the meeting place of an aristocratic scholarly society.

Partially collapsed lava tube and cave system complete with concert hall, underground pond, and unique albino crabs.

The final resting place of the great navigator, or maybe his brother.