See the imprints of ancient trees, burned and preserved by lava.

This museum focuses on the history and culture of the German settlers in Pennsylvania.

The bones of the Biblical Magi traveled to Constantinople and Milan before landing in their current home inside an elaborate golden reliquary in the Cologne Cathedral.

A terrace reminiscent of Rome's Spanish Steps is tucked away in a little park in Washington, D.C.

In suburban Maryland, a tree grown from seed flown to the moon stands almost forgotten.

An American industrialist hoped this nature preserve could help save the North American bison.

Where three rails and three centuries of transportation meet.

10,000 flowered plants bloom in the City of Roses.

There has been an astronomical clock on this spot since the 14th century.

A small park honors the legendary Ukrainian poet.

Constrained by time and topography, this civil engineering landmark was constructed 100 feet above Starrucca Creek over the course of a single year.

A glimpse of the Pacific Northwest‘s indigenous culture in Washington, D.C.

This iconic neon jester is a local landmark that you might recognize from his cameos in film and television.

A gift from Japan, 17th-century lantern stands among the cherry trees at D.C.'s Tidal Basin.

A larger-than-life monument to the inventor of the Bunsen burner.

The United States' only educational center specializing in disease vectors and mosquitoes.

The highest point in Washington state is a volcano covered in glaciers.

Stroll through a wonderland of stupendous moss-covered trees.

A tiny red pebble marks what may be the quietest outdoor spot in the United States.

Somber memorial to the May 10, 1933, book-burning which took place on this spot.

Step aboard the first ship to circumnavigate North America.

A 1,000-foot-long railroad tunnel under Shavers Fork connected the towns during West Virginia's logging boom until its closure in 1985.

A small hippo-shaped fountain in Berlin, Germany.

This landmark vessel dry-berthed in Tacoma's harbor served in emergencies and ceremonies for more than 50 years.