Several of these strange cone-shaped bunkers can still be seen around the former Nazi headquarters.

The oldest still-operating tavern in the United States was once owned by a pirate.

Legend tells how a Spanish soldier disappeared from this isolated sentry box without a trace.

A pyramid commemorates the birthplace of James Buchanan, the 15th president of the United States

An iconic photograph from the Spanish Civil War saved this shrapnel-scarred historic house from destruction.

Poet William Blake penned some of his most famous work during his brief stay at this beloved country cottage.

This campus museum commemorates a national tragedy.

These tiny statues form a terracotta army from China's Han dynasty.

This memorial to the Mercury Seven astronaut stands at the site of his former elementary school.

Walk through a restaurant's refrigerator door to reach this hidden bar.

The pharmacy's retro ice cream mixer is one of the last of its kind.

It marks the spooky spot where the bodies of two young boys were found in the 19th century.

A memorial marks the library lobby where Langston Hughes' ashes are buried.

The second-oldest garden cemetery in the U.S. was also a college brainstorm spot of Stephen King.

This super-sized statue is the only public memorial to the deal that ended America's neutrality during World War II.

This gigantic monument hidden in the woods was built to thank the Dutch for sheltering Belgian refugees during World War I.

Never actually a tree at all, this spot was the site of London's public hangings for nearly 600 years.

These enigmatic columns tower over the ruins of an ancient Toltec city.

The first permanent memorial to a unique secret weapon of World War II.

Located just behind a quiet residential neighborhood, this is ground zero for the Salem witchcraft hysteria of 1692.

The train platform where Jews were sent to concentration camps is now preserved as a Holocaust memorial.

It marks the spot where the high-ranking British officer died during the Falklands War.

A small cemetery remembers the British troops who fell during the Falklands War.

A hilltop collection of crosses remembering the hundreds of Argentine troops who fell during the Falklands War.