An inconspicuous footbridge beloved by San Diego locals.

San Diego's most historic and haunted home.

Behind this beachfront shop lies a spectacular, colorful sea cave with an equally colorful past.

Fittingly, America's museum of architecture is itself a magnificently designed old building.

The most decorated dog of World War I is preserved in the Smithsonian.

Home to items never before seen by the public.

Long-abandoned trolley tunnels just a mile away from the White House are turning into an art space.

The former home of the hard partying literary power couple is now one of the only museums devoted to their story.

One person's lost luggage is another person's treasure.

A graveyard of bathyspheres and diving bells paints a weirdly accurate account of ocean exploration's rickety history.

Tucked away atop a quaint Alabama pharmacy is this tiny display of antique medical tools.

A local landmark with generations of spraypainted messages, and more being added each day.

A local scoured more than 1,000 acres for stone to create his masterpiece.

Home of an evil witch famous within southern folklore.

The world's longest known cave system.

The first full-scale tunnel built in America is short but scenic.

One Confederate statue that accurately reflects the ugliness of its subject.

This replica of the Greek structure is in the heart of Nashville.

At 135 years old and counting, this historic print shop is heaven for poster nerds and music buffs.

A once-booming Mississippi River town with a history of racial violence is now eerie and mostly abandoned.

Walk the whole Mississippi River!

Knoxville’s architectural icon was the symbol of the 1982 World’s Fair, even catching the googly eye of Bart Simpson.

Just a few miles from downtown Atlanta is a trail covered in a crazy collection of outsider art.

This expansive bridge in the Canadian wilderness was originally just built for friends.