This super steep hike ascends 2,000 feet in less than a mile.

Hidden beneath a bridge, this waterfall is known for the large amounts of graffiti painted on its base.

This Colorado hiking trail provides a small gold mine of abandoned gold mines.

A renovated hotel is bringing new life to a nearly-abandoned mining town in Colorado.

Thanks to a quirk of elevation this gift shop produces magic doughnuts that are found nowhere else on Earth.

The largest source of fossilized insects anywhere.

The museum chronicling a treasure hunter's dream, fulfilled.

San Francisco's oldest surviving monument and meeting place for 1906 survivors.

The second building of its name to occupy this location might be the finest flatiron building in San Francisco.

A speck of nature and art in one of San Francisco’s most notorious neighborhoods.

The last remaining relic of San Francisco's glittering 1915 Panama Pacific Exposition.

The giant pair of sexy legs sticking out the window of this costume store have become its main draw.

Not merely a museum – but a whirring powerhouse that offers a subterranean peek into the heart and soul of cable car operations.

A still functioning vaudeville carousel that has operated for over a century boasts a colorful menagerie and past.

In all of the 29 years it was in operation, no prisoners ever escaped successfully... or so they claim.

The ruins of a town wiped out by the second-largest earthquake in recorded history.

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.

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

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

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

A sewing machine tycoon built this miniature castle for the people and to beautify a lakeshore.

This restored house is like a time capsule of the president's unconventional inauguration.