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

Amid the sprawling Defense Intelligence Agency Headquarters is one of Washington's least accessible museums.

The famous abolitionist’s preserved estate is one of Washington's finest monuments to its great Black citizens.

The U.S. Navy’s preposterously detailed mini battleship took 77,000 hours to complete.

The country's oldest continually-operated mini golf course lies hidden in plain sight, eclipsed by one of D.C.'s most popular tourist attractions.

This lovely pocket park is one of the most under appreciated in D.C.

A secret greenspace hides atop a Capitol parking garage.

Rumor has it the uncarved lump behind the three famous suffragists is reserved for the first woman president.

Corn-inthian columns with a uniquely American take on neoclassical architecture.

This unique historical monument features large concrete spheres designed to resemble fallen stars.

Railroad officials in the early 1900s sought to spare travelers the sight of Roman soldiers’ private parts.

A hidden gem on the lawn of the U.S. Capitol Building designed by landscape architect Frederick Law Olmsted.

Need a hardcopy of the 50-title Code of Federal Regulations? This is the place.

A wondrous old library overlooking the nation's capital.

A hoard of sky catalogs, astrophysical journals, even the works of Galileo and Copernicus.

The 28,000-year-old specimen is remarkably intact.

America's Most Wanted's set resides in this tribute to the history of crime and punishment.

The Byzantine, pre-Columbian, and medieval art at this stately mansion are some of the most under-appreciated collections in D.C.

For 60 years, the academy had no permanent location until members voted Washington D.C. as its forever home.

The beloved statue at the National Academy of Sciences is oh so inviting to sit on.

During the Industrial Revolution this “Temple of Invention” was full of intricate miniature machines and gadgets.

A historic estate packed with George Washington's heirlooms, and its own nuclear bunker.

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

On rare days, this abandoned castle's gatekeepers open its doors, revealing the eye-popping splendor hidden inside.