Visitors dating back to the 1600s carved their marks in the stones of the iconic tower.

Walk along the medieval fortifications that have been protecting Tallinn since the 14th century.

Now harmless, this looming post struck fear into the heart of medieval troublemakers.

One of the best-preserved Roman amphitheaters is still used today, but for less brutal events.

A musical instrument played by the sea.

A chain of 16 wondrous lakes formed as a result of the gradual dissolution of soluble layers of bedrock.

The remains of the last Bosnian fortress to fall to the Ottomans are still standing.

This picturesque monastery at the base of a cliff is a peaceful oasis open to all visitors.

Oriental bazaar in the heart of Sarajevo.

This cluster of little wooden huts once ground local farmers’ wheat into flour during the days of the Austro-Hungarian Empire.

Bridge that died in war and was resurected.

There's a mini version of Iguazu Falls hidden in the Balkans, and it's got a rope swing.

A little sculpture with a large wardrobe.

This fairytale castle was built as a show of power but was nearly torn down thanks to its history of torture.

Climb inside an iron crystal magnified 165 billion times its normal size.

An Austrian house of bones filled with hundreds of intricately painted skulls.

Terrifically morbid cemetary and site of famous Paracelsus' grave.

Built to give thanks for the passing of a plague epidemic, this cathedral is a one-of-a-kind architectural hybrid.

An Albanian monument to the Communism that nearly crushed the country is now a crumbling wreck.

An important Mayan religious and trading center dating back to 200 BC.

Commercial airplanes land mere feet over the heads of sunbathing beachgoers on this tiny island.

An old slave lookout in Cuba's historic sugar cane fields.

Once a favorite playground for the world's most illustrious guests, Hotel Nacional's secret weapons and bunkers reveal a more menacing side to its golden history.

Castro's communist ice cream mothership has been serving five-scoop "salads" for over 50 years.