A small window on Via Piella offers a lovely and rare peek at Bologna's lost canals.

In the world's oldest university is a stunning 17th century anatomical theater carved from spruce.

After a nearly successful attempt on Hitler's life, the conspirators met their fate in the courtyard of this Berlin building.

A state-of-the-art medical facility from the Imperial era is now a derelict ruin.

Home to 10,000 medical specimens including the remains of Rudolf Virchow's extensive collection of pathological specimens.

Thousands of coffin-like pillars make up this controversial Holocaust memorial.

A brush maker used his factory to protect blind Jews from the Gestapo.

The largest free-standing aquarium in the world resides in a hotel lobby in Berlin.

Unusual building appears to be haphazardly built from randomly piled bricks.

The charmingly disheveled clock tower of Tbilisi's puppet theater.

These Stalin-era industrial 'death traps' hang lifeless above the city

At this rare mosque in Tbilisi, Sunni and Shia Muslims pray side by side.

An incarceration museum on the spot of possibly the oldest prison in England.

Manhattan’s Battery Park has a whimsical carousel full of spinning, glowing fish.

New York's oldest magic store.

This beautiful building in the heart of Manhattan's Financial District was empty for decades.

An uber-secure, windowless tower of doom in the center of Manhattan is an NSA spyscraper.

Slyly buy a shake in the Parker Meridien lobby.

This massive Brazilian church is built like an angular, technicolor pyramid left by Mayans from the future.

A 125-meter long "tribute to the Brazilian people."

The walls of Germany's Parliament still show the scars of the Red Army takeover in World War II.

Teeming with illegal goods and services, this towering maze of vice is also a popular tourist accommodation.

A "miracle" that seems to produce more holy fistfights than holy revelations.

An unusual round church in London with a Templar past.