Controversial tribute to the heavyweight champion boxer who grew up in Detroit.

To truly appreciate Detroit's landmark skyscraper, you have to step inside.

The concrete shell of an industry giant remains as a playground for graffiti artists, auto scrappers, and paintball warriors.

This sprawling bookstore spans four floors and has more than a million books in stock.

A painted-over wall in Detroit originally built to segregate a black community from an adjacent white development.

Berry Gordy Jr.'s old home was the original headquarters of Motown Record Corporation.

One man's attempt to create an artistic wonder on a run-down block in Detroit.

A Beaux-Arts triumph set to become Ford's innovation campus

Sections of the iconic limestone columns have been left uncleaned as a reminder of the city's polluted past.

This historic Pittsburgh tennis complex is a rare example of natural red clay courts.

Meet your friends, marry your true love, or tell your enemies to kiss your butt under this historic Pittsburgh timepiece.

This public park was the site of the largest civilian disaster of the Civil War.

This picturesque stream was up until recently the site of a ten story mountain of slag and sewage.

Despite being stolen multiple times, this civic electrician's street corner Snoopy won't be stopped.

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

The largest university building in the West is a gothic masterpiece containing dozens of theme rooms based on different countries.

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

A beautiful oddities shop crammed with strange and morbid curiosities.

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

Mutant vegetables, transgenic mosquitos, and atomic rodents span the walls of this one-of-a-kind museum.

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

The anatomical-pathological collection of a man who changed surgery.

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

A historic London pub with prison cells in the cellar and a "spy room" on the second floor.