This New York estate was designed to resemble a medieval Scottish castle.

The second-largest gold nugget in existence, displayed in a Las Vegas casino conveniently named the Golden Nugget.

One of the steepest streets in the United States makes an intriguing challenge for cyclists.

The last remnants of Fort Pitt also hold the distinction of being the oldest structure west of the Allegheny Mountains.

The largest clock face in the United States is twice the size of Big Ben and infinitely more ad-sponsored.

A giant ball made from pieces of an old Jeep.

There aren't too many operational funiculars around, but Pittsburgh has two!

The only way to see Pittsburgh is from the top of this lookout point, just like the ancient members of the native peoples did.

The United States’s oldest funicular railway glides up and down a steep Pittsburgh street.

Found art has transformed this Pittsburgh neighborhood into a psychedelic dream.

Each of these gorgeous, intricately decorated rooms is painstakingly crafted to the scale of 1 inch: 1 foot.

A shining sculpture made of 3,115 lights, the number of visible stars in the Northern Hemisphere.

G.V. Black, the Father of Modern Dentistry, keeps an eternal eye on Chicagoan’s teeth from his perch in Lincoln Park.

This memorial plaque remembers a strangely shallow maritime disaster known as "Chicago's Titanic."

No one knows how many bodies are in this vault in a Chicago public park.

An outdoor urban gallery of large-scale artworks by the world's most influential street artists.

All of Chicago's wood-paved streets are long gone but two alleys remain.

This historic hotel invented the chocolate brownie.

This museum celebrating the almighty dollar lets visitors literally stand in the shadow of a million bucks.

Home to a protest movement, a bombing, and a dramatic change in labor history.

The 606 is a decade in the making.

Designed by Alfred Caldwel, this landscape showcases his vision of a native garden.

A lush green oasis in the middle of Chicago.

The last masonry skyscraper ever built reveals a transitional moment in architectural history.