Ancient serpentine sacrifice holder that has stood the test of time.

This remarkably well-preserved Egyptian plinth is pretty well traveled for a giant piece of stone.

Climb a steep hill in 90 seconds on the second-oldest urban subway in the world.

A gorgeous, Gaudí-esque stairway constructed in the city of Istanbul by a prominent Jewish family.

Known as "Toronto's Flatiron."

One of the largest underground systems runs under Canada's largest urban center.

A miniature representation of Canadian cities and landmarks in incredible—and sometimes hilarious—detail.

The mastermind behind this palatial hotel perished on the Titanic weeks before its grand opening.

These locks on North America’s oldest canal are named after a porcine rock formation.

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

A historic Montreal market that was the city's agricultural hub for over century.

A massive Montreal stadium that has seen nothing but trouble since its inception.

The only example of a Paris Métro sign in use at a subway station outside of the French capital. 

The world's longest known cave system.

The grave of America's 11th president is not in some grand monument but instead it's hidden away on the grounds of the Tennessee Capital.

At 135 years old and counting, this historic print shop is heaven for poster nerds and music buffs.

The Spanish king's private bathroom embraced the idea of a porcelain throne.

It's just another skyscraper, but it's shaped like '90s cell phone.

What was once a unique system of urban elevators is turning into a mechanical ruin.

A graceful natural rock formation stands astride the point where the Gulf of California meets the Pacific Ocean.

Built for the 1962 World Cup, this fully functioning botanical clock is still ticking.

This distinctive Crescent City tradition dates back to the days of horse-drawn carriages.

The scorched Lisbon church that survived two earthquakes and a massive fire.

Hidden beneath a beautiful overlook you’ll find the history of the city depicted in comic strip format next to a pay toilet.