Home to items never before seen by the public.

The oldest building in the District of Columbia was preserved because of a mistaken connection to George Washington.

Iceland's largest lagoon is home to stunning multi-colored icebergs.

The unique waterfall in Iceland's south features a backdrop of geometric black lava columns.

Three columns of volcanic rock shoot out of the ocean.

Strange rock formations tower above the river that snakes through this enchanting Icelandic canyon.

In which a local geological marvel becomes a quaint roadside attraction.

What looks like a simple quaint estate in rural Pennsylvania was in the 18th century home to a small monastic community.

Instruments, apparatus, and rare books all relating to chemistry and its related sciences.

An indoor miniature village and labor of love for Laurence Geiringer, a model railroad enthusiast.

This demolished goliath of American industry once loomed over the depressed town it once made thrive.

A mine fire has been burning under the deserted town since 1962, but this church is still going strong.

No one knows who painted this mysterious mural in a Penn State basement.

J.R.R Tolkien, C.S. Lewis, and other "Inklings" met at the Oxford pub to discuss the now legendary fantasy stories they were writing.

Take a steam-powered ride straight out of the past on this Appalachian rail line.

The last holdout of a pre-Civil War rebel who took the matter of slavery into his own hands.

A 1,215-foot tunnel transports pedestrians beneath the River Thames.

Thanks to modern navigational tools we now know that the true prime meridian runs through a park next door.

19th-century scientists would make the pilgrimage here to verify the precision of their measuring sticks.

The wooden octagon in which Huckleberry Finn and A Connecticut Yankee were born can still be visited in upstate New York.

Curtiss is a forgotten figure in the early history of flight.

Dedicated to the art and science of glass in equal measure, this space is as much laboratory as museum.

This lush forest valley was once mined for lumber to the extent that it was once nicknamed "The Pennsylvania Desert."

Over 100 concrete munitions bunkers are all that remain of a Pennsylvanian village seized by the US government.