Baroque celebration of the end of the Great Plague of Vienna.

The crypt of the imposing Stephensdom holds royal intestines and thousands of skeletons.

Gaudí's famously flamboyant architectural style is on full display in this sprawling park and garden.

Construction of Barcelona's iconic (but controversial) church is expected to be completed in 2026—a century after the death of its architect.

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

An awe-inspiring mosque in Morocco with one of the tallest minarets in the world.

The legacy of a Moroccan Jewish community is remembered at this little mouldering cemetery.

A toweringly silly piece of modern art has been delighting locals since the 1980s.

The only arched bridge made of stone on the entire Mississippi River.

When flour explodes, it's not a pretty sight.

Downtown Minneapolis mixed art and function by turning some of their sewer covers into works of art.

Louise Bourgeois' 30-foot-tall steel spider sculpture.

Venice's island of the dead.

This Venice bookstore has resigned itself to constant flooding by keeping its books in bathtubs and boats.

Go inside to really appreciate this 500-year-old technological masterpiece.

100 year tradition of fist fights, marked by marble footsteps.

Stone Age solar temple is aligned with the sun on each equinox and solstice.

Ancient mysterious ruts carved in the bedrock.

Burial grounds for more than 1,000 bodies deep under the modern town of Rabat.

Two geological phenomena in one precarious locale: a towering stone window, and a deep blue void.

Eighty million natural history specimens call this gargantuan museum home.

The final resting place to 300 Victorian-era pets hides inside the city park.

The popularity of Sherlock Holmes led to the creation of his fictional address, turning the orderly London street numbers askew.

Scattered throughout London are ancient remnants of the city's former bounding wall.