An "inside out" building in the historical center of Paris, featuring Europe’s largest modern art museum.

A visionary precursor to the Internet made of index cards.

Not far from a popular beach, an unfinished, abandoned mansion for Bulgaria's last communist dictator.

One of Jeff Koons’s largest sculptures and his first commemorative work.

This bridge was constructed from the rubble of the infamous Bastille.

Known as the "Dodo Manège," this carousel features a herd of animals that have disappeared—or may be gone soon.

This museum houses an imposing skeleton army comprised of creatures great and small.

Natural history museum celebrating biodiversity with a parade of taxidermy animals.

This triumphal arch celebrating the Sun King's conquest of Lille is a masterpiece of military architecture.

This monumental mural crafted nearly 40 years ago is still in perfect condition.

A copy of the Statue of Liberty greets visitors to the birthplace of Auguste Bartholdi.

Even France's favorite aquatic son Jacques Cousteau, couldn't get to the bottom of it.

Walk through living pictures and music in the Cathedral of Images.

This ancient theater was once the home of fierce gladiatorial battles.

Once known as one of the finest tourist railways in Europe.

The 16th-century church was kept in its ruined state as a reminder of the casualties of World War I.

A magical, macabre wax museum, beloved by locals, uses real artifacts to depict an assassination from the French Revolution.

This recessed garden protects thousands of mountain plants by creating its own microclimates.

The celebrated eyesore created by starry-eyed sweethearts.

The tradition of open-air secondhand and antiquarian bookselling in Paris dates back to the Renaissance.

If you look closely at the oldest bridge in Paris, you might notice hundreds of ugly faces leering from its sides.

This life-size replica of the Statue of Liberty's flame is also a tribute to Princess Diana by default.

A unique tribute to the millions of animals who served and died for the British military.

Famously misunderstood wonder of the ancient world