Live data is transmitted from the Atlantic coast to instantly recreate the ocean waves in this fountain at the NOAA headquarters.

The land is home to swimming ponies and a legendary 18th-century treasure.

The man who first patented the Ouija board rests in peace beneath a headstone that playfully reflects that achievement.

Bubbling up from deep underground is the warm crystal clear water that fills the Warm Springs Pools, America's oldest spa.

These unusual rooms on wheels are holdovers from the 1960s.

The Pentagon sits on a former island that was in Virginia at low tide and D.C. at high tide.

The Grand Ole Opry's big voice came from a small home in rural Virginia where she was eventually buried.

The highest point in Virginia can only be reached by passing through ponies and flowers.

Heron, whitewater rapids, and urban industrialism all add to the beauty of this concrete nature walk.

The most accurate timepiece in the world.

An Industrial Revolution-era public work that purified water using nothing but sand.

An obscure public service from the U.S. government that redeems burnt, moldy, and soiled old greenbacks.

The oldest continuously operating fish market in the United States.

A rotating cast of guys and dolls in front of a Washington, D.C. building.

The national park was once a plantation estate.

A Spiritualist house of worship where believers communicate with the dead in the spirit world.

A three-story tower of books about Abraham Lincoln is one of the more unusual monuments to the president.

Enormous piles of historically significant stones, dumped by Congress in a forest, and abandoned for 60 years.

One of the dwarven trees dates back to 1625 and survived the Hiroshima bombing.

This grand gothic brewery has been pumping out suds for over a hundred years.

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

With over 100 jam-packed rooms to explore plus elaborate tea services and events, the Mansion on O Street is a hidden treasure.

The United States Capitol's former columns still stand.

This colonial tavern played host to George Washington, Thomas Jefferson, and other famous early Americans.