This fort down the Potomac from Washington, D.C. was once the only defensive fort protecting the capital.

Remains of a historic fountain that was mysteriously lost in the demolition of a D.C. traffic circle.

The span is crooked and made from two older recycled bridges.

An allegorical sculpture in Maryland wears the artist’s politics on its trunk.

A tribute to the beloved, kind-hearted "homeless mayor" of Silver Spring.

Giant acorn-shaped 19th century gazebo from which suburban Washingtonians gazed upon the original "silver" spring.

A benevolent, 16-foot-tall river dragon lives on a suburban lawn.

The rooster who crossed the road lives on forever in Takoma Park, Maryland.

A lawn full of retired spacecraft on display at one of NASA's first research labs.

The development and impact of electronic media showcased in a picturesque farmhouse in Maryland.

William Blake claimed to have painted this gothic masterpiece after encountering this nightmarish being in a vision.

This taxidermy horse was a Civil War hero.

The largest puppetry museum in the United States houses the world's most complete collection of Jim Henson artifacts.

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

The United States Capitol's former columns still stand.

Art deco landmark on the outskirts of Washington, D.C.

Once the supplier for noteworthy projects like the National Cathedral, this old brickworks now lies abandoned.

This giant iron playfully pays tribute to an early 20th-century architectural trend.

The blinking light atop the iconic landmark has been sending secret messages for decades.

One of the most influential presidents in U.S. history wanted only this plain, elegant monument as his lasting memorial.

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

A bas relief commemorates the "Nuns of the Battlefield" who cared for soldiers on both sides of the conflict.

This grisly headstone doesn’t seem to be resting in peace.

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