The largest hot spring in the United States is, as the name suggests, a stunning show of natural color.

New fungal and bacterial species call this deadly lake home.

Mining town from the late 1890s, once home to Calamity Jane.

The United States Capitol's former columns still stand.

The privately owned cemetery that holds room for Washington's finest when they step down from life.

Parking garage where Bob Woodward met Watergate source "Deep Throat."

The house where John Wilkes Booth conspired with his co-conspirators.

A monument in Washington D.C. marks the spot from which all other roads were supposed to stem.

Peek through the gates at this oasis from the city, full of Old English charm.

This once-grand marvel of engineering is now 41 miles of scenic hiking trail.

The oldest house in Manhattan is now a museum that remembers the home's sordid history of scandals, vice-presidents, and ghosts.

A discreet little stairway on St. Nicholas Avenue leads to a quaint and unexpected cobblestone street of 19th century wooden rowhouses.

The famous author's cottage hideaway.

Manhattan and the Bronx have been playing tug-of-war over this former island neighborhood for more than a century.

The home of one of America's most wealthy industrialists is now a historic site that remembers a more decadent time in the country's history.

Captain America, Sub-Mariner, and the Human Torch were all born in this art deco Manhattan masterpiece.

On the side of a remote mountain, a stone face bearing an inscription of mysterious origin.

Here lies Lilly E. Gray, an alleged "victim of the beast," but the reason long remained a mystery.

Dig for your own trilobites in this goldmine of invertebrates.

A replica that won't float away.