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

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

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

A treasure trove of Renaissance-era funerary art in a Roman church built on top of Nero's grave.

An ancient knight and a symbol of the city's freedom.

A wunderkammer of gold and silver reliquaries and ancient saintly bones.

Ancient snack bar of the Roman Empire re-opened.

Museum dedicated to "the man who moved the Earth."

The former Nazi Germany concentration camp stands as a museum to remember this dark chapter in European history.

The site of many battles and tragedies, including the 40 maidens who leapt into the sea.

These mechanical goats first battled it out in the year 1551, all because of an overcooked deer.

A unique book shop with a collection of rare tomes and a nostalgia museum.

A copy of the famous statue can be found in this Florence piazza, along with one of the most breathtaking views of the city below.

This strange bovine gargoyle is said to have been put in as a passive aggressive form of revenge.

This once-grandiose behemoth of a monument from the socialist era now sits quiet and closed up.

The last moments of the ill-fated Pompeiians, frozen forever in plaster.

Pompeii's less famous neighbor is still revealing her secrets.

Polish luminaries and masterful folk art find sanctuary in this unique cemetery.

The most famous location in China was home to whole dynasties worth of imperial rulers.

This smaller cousin of the Forbidden City has gone from ancestral sacrifice to tourist's whispers.

This probably wasn't what Mao had in mind.

The embalmed remains of the communist leader lie within a custom crystal coffin.

A mysterious castle built as a monument to lost love.

A historic presidential getaway on the continental United States' southernmost island.