Ninety feet off the valley floor is an ancient dwelling put under protection of the U.S. government by Teddy Roosevelt.

Most-visited and most-photographed slot canyon in the American Southwest.

Dramatic river bend surrounds a natural red-rocked pedestal.

This small interfaith chapel lies not far from the rim of the Grand Canyon.

A mysterious spirit totem at the edge of Navajo lands.

More than a century old, this trading post resides in the Navajo Nation.

One of the most extensive and well-preserved collections of dinosaur footprints in North America.

A spiritual vortex among the red rocks in Sedona.

The world's only teal arches exist in a city that cares more about its aesthetic than an Instagram influencer.

The longest-covered bridge in the state of Maryland.

This three-story Victorian mansion is now home to the National Park Service’s Historic Preservation Training Center headquarters.

A well-preserved quarry and six of eight continuous burning pot kilns used to make burnt lime and crushed stone are highlights of the self-guided walking tour in Fountain Rock Park.

Take a trip to the past aboard a 1920s railcar or open flatcar for a scenic ride through Maryland farm country.

Washed out by the Johnstown Flood in 1889, the surviving portion of the original two-span bridge now resides at Fishing Creek.

The remains of a historic plantation nestled in between a parking lot and the rental car return at Reagan National Airport.

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

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

A superbly preserved example of Georgian residential architecture that was once home to one of the founders of Alexandria, Virginia.

This small pedestal marks the spot of the first lot of land sold in Alexandria, Virginia in 1749.

An original apothecary from 1792.

A massive, majestic mammal watches over pedestrians from his perch atop a former B.P.O.E. lodge.

The final resting place of an unidentified revolutionary soldier sits behind a Virginia church.

This brick-lined pedestrian walkway was once a railway tunnel used during the Civil War.

Once the largest trading firm of enslaved people in the U.S., this building is now a museum that preserves Alexandria's dark past.