A chain of 16 wondrous lakes formed as a result of the gradual dissolution of soluble layers of bedrock.

A peculiar mansion built by the troubled heir to the Winchester Rifle Company fortune.

Frank Lloyd Wright’s most iconic home dangles over a Pennsylvania waterfall.

This bug-eyed water wheel uses the power of the Sun to clean up Baltimore Harbor.

This plaque marks a place where one of Hollywood’s most famous dancers got his start.

Color-coded signs direct drivers on a network of routes designed to avoid Pittsburgh traffic.

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

A portion of the old Pirates stadium over which a defining home run once flew still stands even after the rest of the stadium was torn down.

A model of a dinosaur that was named for Andrew Carnegie stands outside the museum that also bears his name.

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 restored Pittsburgh house of God has been converted to a marvelous house of suds.

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

An artist's cute bronze subway sculptures belie his violent artistic past.

A bit of retro transportation flair preserved in the world's largest department store.

A band of aerialists and circus performers putting on incredible shows in East Williamsburg.

Lie in a hammock where George Washington stood.

This mosaic dedicated to John Lennon was tended for years by a Beatles super-fan.

This sculpture by artist Fritz Keonig survived the 9/11 attacks and now stands as a monument to the victims.

Wall Street has a new heroine, a bronze statue of a small but fierce girl.

A three-story copper skybridge connects two Manhattan buildings with Art Deco luxury.

This whimsical group of statues is a favorite of children who love to climb all over Lewis Carroll's beloved characters.

This cemetery has graves dating back to the 17th century, including the city's oldest carved tombstone and an ominous cryptogram.