This lonely waterfront memorial to the men of the Titanic was erected by the "Women of America."

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

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

This stunning blue and gold room changed cities twice before becoming part of the Smithsonian.

The winding route passes through an enclosed alleyway, two tunnels, and leads to the White House basement.

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

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

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

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

A cavernous three-story, 43,800-square-foot basement that was forgotten about for 60 years.

A painfully obvious spy house sits right across the street from the Russian Embassy.

A tiny piece of the Moon is embedded in this stained glass masterpiece.

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

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

The final resting place of a physician rescued during the bombardment of Fort McHenry.

This statue of two men in a rowboat was erected to honor those who died while fishing in the Chesapeake Bay.

George Washington once stopped by this house for dinner.

This memorial honors five journalists who were killed in a mass shooting in 2018, and affirms the importance of the first amendment.

Using a massive antenna made up of five miles of wire, two scientists tuned into organic radio waves from the planet Jupiter.

This statue honors the author's groundbreaking family story.

The oldest military monument in the United States.

Just outside the Naval Academy, Hell Point is a historical marker that could easily be the point where failed students wait for the bus.

Historic barracks utilized during both the Revolutionary War and the Civil War.

The elevator hidden in a smokestack on Roosevelt's yacht now serves as a monument to the former president.