The ruins of this Thomas-Jefferson-designed mansion have been left to crumble since the Christmas Day they burnt down.

This field of concrete was once an active defense site armed with nuclear warheads.

This tree is a living witness to the beginning of the Civil Rights Movement.

At Brandy Station, Civil War soldiers left their mark on the battlefield and the walls of this small wooden house.

This tower was once used to create ammunition for early settlers.

This monument is dedicated to those lost on June 6, 1944, in the town with that day’s highest per-capita casualty rate.

Memorial stone for GWAR vocalist, depicted in his iconic costume.

This pun was simply waiting to come to life, and one defense contractor made it so.

This simple stone memorial remembers a secret, Geneva Convention-defying interrogation base from WWII.

This twice-relocated "Usonian" home is among the smallest built by master architect Frank Lloyd Wright.

The solitary grave of a schooner captain killed by lightning while serving biscuits.

Anna Anderson spent most of her life claiming to be the lost Romanov child Anastasia.

The only museum outside of Australia dedicated to exhibiting the artwork of Indigenous Australian artists.

The tomb was guarded by soldiers from both sides of the war, and some left their initials carved in the brick.

The biggest exposition of dental equipement in Europe. And a Mummy.

This 13th century Gothic brick castle is the largest in the world by surface area.

The silly symbol for an underground protest group is now scattered around the city.

Learn the fine art of making a centuries-old treat at this hands-on food museum.

A 20th-century picture show in 3-D.

This now-defunct synthetic fuel plant was once a major cog in the Nazi war machine.

These ancient sacred grounds granted amnesty to those who managed to reach them.

A cooled lava flow from the Haleakalā volcano formed these surreal-looking columnar basalt structures.

Formerly a lovely white sand beach this Hawaiian stretch is now a trap for countless tons of trash.

Air-raid tunnels hidden beneath this opulent hotel provided shelter and an escape route—and one of the world's longest slides.