One of the largest artillery pieces in the world sits in a Washington D.C. parking lot.

A clone of a cloned tree that was so important it allegedly had its own guards.

She stares out across six lanes of traffic, clutching a musket and infant with determination.

This downtown Dallas art installation is always on the lookout.

Locals dubbed it the "Owl Building" because of its bird-like appearance.

The upstairs reading room is packed with millions of rare books, literary manuscripts, and historical treasures.

Turning night into day in Victorian-era Austin to thwart a serial killer.

This failed condo development was reborn as a street art hub.

Home to the largest urban bat colony in North America, estimated at 1.5 million bats.

One part antique store, one part curiosities hodge-podge.

This unique structure in suburban Austin is made up entirely of other people's castaways, and constantly changing.

Continuing the tradition of the dime museum in style.

A grove of colossal man-made flowers built to collect the sun's rays.

A trio of colossal statues spread across a Dallas neighborhood chart the emergence of a giant robot born of a locomotive and spilled gin.

This collection of bronze hands comes from astronauts, presidents, baseball greats, and more.

America's first federal monument.

This grave marks the passing of a historic Jane Doe whose identity remains a mystery to this day.

A muscular Art Deco monument represents the struggle between regulators and unbridled markets.

A 1,100-ton train fell through the floor in 1953. Workers got it patched up in just 72 hours.

A rotating cast of guys and dolls in front of a Washington, D.C. building.

After his presidency, George Washington planned to live only a few blocks from the Capitol building.

An overlooked memorial honoring the local Washington residents who died in World War I.

The institution is sitting on a goldmine of 21,000 paints, varnishes, pigments, and primers preserved for posterity.

A line of blue paint marks the route of the inaugural parade.