These official units of measurement—including chains and perches—lie hidden beneath tourists' feet in a popular London hub.

The "lost friend” is the most famous of the six moai statues that were removed from Easter Island.

A set of medieval stained-glass windows tell the gruesome story of a Viking siege.

This long-hidden space above Westminster Abbey now displays the battle gear of the legendary King Henry V.

This tree was grafted from the actual tree that led Isaac Newton to ponder the theory of gravity.

This unassuming alcove in London’s famous Tower Bridge once served to capture, store, and display dead bodies from the River Thames.

A defensive structure built during the Hundred Years War has remained useful in one way or another for nearly 700 years.

In the 18th century, the Earl of Buchan mapped the universe on this stone pillar.

The oldest bridge in South Carolina may have been designed by the same man who created the Washington Monument.

This bare tree might not have leaves but it is constantly clothed in festive decorations left by mysterious local benefactors.

Despite being burnt down multiple times, the ruins of this South Carolina church are still standing.

A quirky Poe-themed joint on an island keen to celebrate its overlooked connection to the famous writer.

The final resting place of the Seminole Indian chief who fought against government occupation in Florida.

One of the oldest living oak trees in the Southeast.

Thirteen pastel palaces in downtown Charleston add a gorgeous splash of color to the city.

South Carolina's last remaining slavery auction house is now a museum devoted to its own tragic history.

This small memorial is almost as well concealed as Smalls himself was on the night he sailed to freedom.

Charleston's historic city jail once held everyone from pirates to Civil War POWs.

This recently rediscovered Civil War-era submarine was the first to ever sink an enemy ship.

An old train trestle re-imagined as an Egyptian obelisk.

A handful of beehive kilns are all that’s left of a historic brick-making empire.

This lovely burial mound is actually a replica that was installed after archeologists excavated the original.

Six ravens are kept captive (but well-fed) at the Tower of London to prevent the fall of the Crown.

The world's largest fire hydrant is supposedly tornado-proof.