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

An unassuming, powerful monument north of the U.S. Capitol bears witness to the resilience of Japanese Americans during a time of grave injustice.

The district's only illusionarium supports free writing programs for local students with every purchase.

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

The remains of Martha, the last known passenger pigeon, serve as a tool to educate about conservation.

These recently uncovered walls are all that's left of Washington, D.C's first defense contractor.

Astonishing collection of helmets, scientific instruments, and medical models.

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

The narrowest house in America is seven feet of pure spite.

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

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

The hidden offices underneath Memorial Bridge have been locked up since 1976.

On the Irish coast, 18 members of the Howard family are eternally resting in an Egyptian pyramid.

This magnificent mausoleum is as much a work of art as it is a historic resting place.

The innocent intentions of this monument are somewhat lost in the sculpture's muscled imagery.

This forgotten boat elevator was an engineering marvel in its heyday.

This robust fence in front of a historic Georgetown home is likely made from hundreds of recycled Revolutionary War firearms.

The world's oldest soul food restaurant is also one of its best.

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

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

A museum cafe showcases Native American dishes and indigenous ingredients from across the Western Hemisphere.

A lovely aquatic park built by a one-armed Civil War veteran who made a fortune from lotuses.

A historic neighborhood church is reborn as a psychedelic arts collective.

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