The tea room that pushed the boundaries of adorable straight into... we can't find the words.

400 million-year old limestone caverns nestled in the Ozarks served as shelter and a hideout for cultures throughout North American history.

This partially buried wreck is one of the most complete of its kind but is only revealed when the sea allows.

The rusting remains of the largest assembled WWII fleet on the West Coast.

The semi-reclaimed ruins of this canal were once part of an ambitious plan to reroute the mighty potomac.

At Washington's Dulles Airport is a satellite museum (no pun intended) with three quarters of a million square feet of aircraft history.

This pre-Revolutionary War grist mill ground corn and flour for soldiers in seven American wars.

Daily lunch spot for many of Washington, D.C.'s cab drivers.

Light bulbs, scrap wood, and tinfoil comprise this homemade throne of the gods.

A small triangle of DC grass is the final resting place of one of Sonny and Cher's songs.

The longest escalator in the Western Hemisphere takes over three minutes to ride down.

Prone to disastrous fires, the city of San Francisco has the Guardian, a fireboat gifted by residents, to watch over them from the bay.

A classic advertising icon immortalized in regal bronze.

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

A nondescript building that's been functioning as a speakeasy for nearly a century and a half.

Standing in for the first ship to navigate the Northwest Passage.

The key to turning shifting dunes into the green oasis of Golden Gate Park.

Once the largest windmill outside of Holland, with enormous 114 foot sails.

This turn of the century masterpiece has a mysterious goaty interloper.

An overlooked and unassuming engineering marvel.

A huge musical instrument played by the ocean.

A modern mechanical planetary system, part of a 10,000 year clock.

A Barbary Coast watering hole built into a Gold Rush shipwreck.

The largest whiskey stash on the West Coast survived the 1906 fires--but not without heroic effort.