The history of the tea trade is told in bas-relief on this historic pair of Boston doors.

America's original house of worship for Spiritualism, the religious movement based on communing with the dead.

The site of Paul Revere's historic two lantern warning.

The massive machine creates cracking displays of indoor lightning.

Radical Bookstore and Community Space.

Berthed at the Charlestown Navy Yard in Boston, "Old Ironsides" is the oldest commissioned warship still afloat.

The site of one of the strangest disasters in history—a wave of deadly molasses traveling at 35 mph.

The American Revolution was galvanized into serious action due to the tragic clash with British soldiers that occurred at this location.

The often-overlooked ruins of one of the first buildings designed by famous landscape architect Frederick Olmsted.

One of the now-less-hidden floral gems of the "Emerald Necklace."

Macabre headstones carved with winged skulls, dancing skeletons, and pithy reminders of impending death.

This razorback ridgeline has doubled as a scenic drive since the early 1900s.

The final resting place of American icon Buffalo Bill, and a museum that aids in telling his tale.

The clock that sets them all.

An impressive collection of over 50,000 minerals including moon rock from the Apollo 17 mission.

Hidden beneath a bridge, this waterfall is known for the large amounts of graffiti painted on its base.

The ancient dwellings of the Puebloans, located in the cliffs of majestic mesas.

When ecosystems collide in the arid Southwest.

A breathtaking array of ancient Pueblo structures and artifacts counterintuitively preserved by neglect.

The largest self-built castle in the U.S., six decades in the making.

Strange red rock formations that have been attributed to a higher power for hundreds of years.

The Old Courthouse takes visitors on a captivating trip through St. Louis' timeline.

The "lovely red Vega" of the legendary record-settling pilot.

An overlooked oasis of quiet on the grounds of Washington's monumental basilica.