The history and future of cannabis.

This 22-floor tower's Skydeck offers panoramic views of Amsterdam.

This gorgeous reading room houses the oldest and largest art history library in the Netherlands.

Established in 1638 to battle the Black Death, Hortus Botanicus Amsterdam is a treasure trove of rare flora.

Museum preserving torture methods from the past.

Amsterdam's narrowest house facade is a monument to 17th-century tax evasion.

This bronze statue of Martin Luther King was placed in the park without permission.

The ruins of this medieval castle on a foggy hill tell the story of a once-mighty empire.

Structure built from the skulls of vanquished foes.

This 14th century castle withstood years of battle but is now sliding off the hills into the Danube.

Statues of two of Srem's most well-known animals.

At this archaeological site, visitors can explore the ruins of the capital of the former Roman province of Moesia.

The interior of this Serbian royal family's mausoleum is covered with exquisite mosaics.

This spaceship-like Serbian monument reaches for the stars in celebration of the fallen fighters of fascism.

In the hinterlands of Serbia's capital, a giant reflective mushroom houses an aeronautical history of the former Yugoslav republic.

Near Belgrade, an ancient-looking sarcophagus serves as a World War I monument.

A pair of connected skyscrapers form this symbolic gateway.

A small memorial to a deadly night in Serbia that shook the world before it was swept under the rug.

A Serbian church lit by chandeliers made of weapons.

A towering spire in the fortress of Kalemegdan honors the victorious armies of Serbia during their struggles against the Ottoman Empire.

The unusual sculptures are believed to be powerful political symbols.

Ride in 1960s style on the private luxury train Marshal Josip Tito used to travel around Yugoslavia.

Nikola Tesla's ashes are held in a golden sphere, surrounded by his works.

This art installation pays homage to the famed stones of European lore.