Perhaps the most spectacular grotto along the Algarve coastline.

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

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

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.

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

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

This rusting artillery is a relic of Vichy France's influence in West Africa.

West Africa's largest fishing port honors its artisanal fishing process.

This tiny, tranquil Senegalese island serves as a powerful symbol of the Atlantic slave trade.

This abandoned bunker looks out over the Atlantic from its clifftop perch.

An island made out of shells, including a cemetery.

This giant statue is the product of a mixture of corruption, Stalinist architecture, and North Korean manpower.

Despite a fraught and controversial history this African island holds a powerful monument to the tragedy of the slave trade.

This deceptively salty lake looks like blushing pink lemonade.

A smoky doorway in Dakar leads to one of the city’s great communal eating experiences.

Dakar is home to one of the oldest African art institutions in West Africa.

The Sighignola summit on the Swiss border offers views so breathtaking it's been named one of the most beautiful places in Italy.

A historic observatory precariously perched at the "Top of Europe."

The second-highest train station in Europe.

This historic covered bridge contains a series of macabre paintings that communicate one thing: everyone dies.

A once-thriving hotel in the Swiss Alps couldn't compete with climate change.

A tower-like theater in the Swiss Alps built to withstand the high winds and avalanches of the mountain pass.

Legend has it this fountain built to symbolize the Pope’s power hides a strange secret concerning Neptune's manliness.