This grinning pup statue is all that's left of what was once a ubiquitous Bay Area diner chain.

Another of California's unused Cold War missile defense complexes has become a graffiti gallery.

A rough granite monument marks the spot where Europeans first caught sight of the San Francisco Bay.

Beneath the southern end of the Golden Gate Bridge is the “Gibraltar of the West Coast,” a fort built to protect the San Francisco Bay from naval attack.

Sitting atop San Francisco's tallest hill, a cross honors the victims of the Armenian genocide.

The world's largest second-hand graces a clock surrounded by constantly changing flower beds. 

One of the few remaining ancient aqueducts described by Frontinus as 'the most solemn testimony of the Empire.'

This historic black and white monastery is one of Bulgaria's architectural jewels.

Down the road from where the Wright brothers lifted off is another flight tribute practically hidden from sight in the woods.

A derelict bit of transportation infrastructure hidden in the woods.

The king of U.S. high points towers over every other peak on the continent.

Considered by many to be one of the most dangerous highways in Alaska.

Clean, cold drinking water flows from a nondescript pipe in a roadside rock face.

During the summer, surfers in Alaska take advantage of this inlet’s unusual water patterns.

Running under an entire mountain, the longest highway tunnel in North America is kept fresh using portal fans and jet fans.

This WWII-era military installation once held an entire city within its walls - now, its walls are falling down.

This small city where almost everyone lives in the same building can only be reached via North America's longest tunnel.

Buy your friend a drink or staple some cash to the wall for the next guy at the Salty Dawg Saloon.

The largest hot spring in the United States is, as the name suggests, a stunning show of natural color.

A beautiful geyser under environmental threat.

One of nature's most well-scheduled phenomenons resides in Wyoming's Yellowstone National Park.

This Yellowstone geyser may not shoot as high as the nearby Old Faithful, but it erupts for considerably longer.

The largest island on the great salt lake is home to curious creatures and strange stories.

The ancient dwellings of the Puebloans, located in the cliffs of majestic mesas.