Captain John Smith thought these cliffs were amazing in 1608 but sharks thought so 20 million years before him.

Once home to seven different roller coasters, Glen Echo has undergone many transformations since its founding in 1891.

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

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

Eighteen miniature death-scene dioramas.

This isn't your average roadway—it's actually a National Park and a transportation pioneer.

A former major munitions plant that has been converted into a sprawling art space.

Herbert Hoover's "Brown House" rural presidential retreat was a PR disaster amid the start of the Great Depression.

This lovely picnic spot featuring thunderous jet landings is an aircraft spotter’s dream.

This colonial tavern played host to George Washington, Thomas Jefferson, and other famous early Americans.

The rogue roots are gradually consuming some of the historic marble grave markers.

The Virginia farm where John Wilkes Booth met his grisly end is now largely forgotten.

At 207 feet, one of the world's longest continuous escalators.

This pre-Revolutionary War grist mill ground corn and flour for soldiers in seven American wars.

An original apothecary from 1792.

The state bird of New Mexico, constructed entirely out of garbage.

This playground sculpture of an icon from the past is dedicated to the children of the future.

The decorations were inspired by an unlikely missing treasure.

A derelict bit of infrastructure from the canal that once ran through D.C. is landlocked in the heart of the city.

Look closely and you’ll notice that the color changes a third of the way up the tower.

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

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

A much-maligned monument to teetotalism.

Washington's iconic carousel has a nice piece of Civil Rights history.