This old ruin once served as a post office, a train station, a restaurant, and a bridge to the Atomic Age.

A small metropolis of Pueblo cave dwellings have been carved right into the hillside of this national monument.

This building is a recreation of the gatehouse that separated Los Alamos from the outside world during the era of the Manhattan Project.

Once a dining hall for boarding school students, this lodge was a popular haunt for nuclear physicists working on the Manhattan Project.

A monument dedicated to a local softball team full of clowns.

The 7,000-year-old calcium carbonate formation creates a magnificent natural bridge.

This sundial indicates the time based on where you stand within it.

A phenomenal assembly of pueblos in New Mexico is the most complete example of ancient ruins north of the border.

A boulder so big and tough, they had to turn it into a landmark.

The giant stump of the once towering cottonwood where Ute people held tribal meetings.

This monument is dedicated to Balto, the heroic Alaskan sled dog.

The lesser-known Alice sculpture of Central Park dedicated to the “godmother of American children.”

Built hundreds of years ago this downtown iron barrier once protected a much despised king.

Curious crustaceans support an obelisk from ancient Egypt that now stands in modern-day Central Park.

The only home that Alexander Hamilton ever owned has a history almost as troubled as his own.

This ruined fort hidden at the top of Central Park can't seem to keep from losing its historical plaques.

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.

Amid the bustle and noise of the Financial District hides a secluded garden oasis above the city streets.

A vibrant, 100-foot-tall mural dedicated to Evelyn Nesbit, the tragic icon of the Gilded Age.

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

A 19th-century politician who died after walking home in a blizzard is honored with this Manhattan statue.

Named the fifth most beautiful building in America in 1885, this former courthouse boasts the best view in the Village.

This wall on a street corner in Lower Manhattan has been a blank canvas for a rotation of renowned artists since the 1980s.