This statue of one of baseball’s greatest pitchers looks like something out of a sci-fi horror movie.

The U.S. Fish Commission’s effort to mass produce carp.

Four bald cypress trees in Lafayette Square, across from the White House, mark the southern edge of a 100,000 year old cypress swamp.

D.C.'s first central library was born out of a chance encounter with the philanthropist whose name it bears.

The towering figures were created from the cemetery's fallen old-growth trees.

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

Sit where JFK proposed to Jackie or where Nixon dined on meatloaf at this storied pub.

The house where John Wilkes Booth conspired with his co-conspirators.

The unique traffic pattern named for an influential urban planner is also known as the Pedestrian Scramble.

An unusual sculpture, an interesting history, in a strange place, for a good cause.

A small token of gratitude from freezing cold journalists who were given a warm haven while covering JFK's inauguration.

A haunting tribute to pioneering photographer Clover Adams.

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.

The bridge's highly-contested plaque (once again) honors Confederate President Jefferson Davis.

Proto-CIA agents trained with grenades in the sand traps and fired machine guns from the fairways.

An astounding collection of medical specimens, including bits of President Lincoln.

A local farm's collection of unusual structures from a now defunct storybook amusement park.

Dogs, cats, horses, monkeys, frogs, and fish are laid to rest at the second-oldest pet cemetery in the U.S.

This four-story steel sphere in Maryland was used to test biological weapons.

Three abandoned missile silos are hiding in plain sight behind a suburban development in Maryland.

The final resting place of the tragic king and queen of the Jazz Age is tucked away in a small Maryland graveyard.