There are many Byzantine-era churches still standing in Athens, but this is the only one with a 2,500-year-old column rising through its roof.

This striking sculpture of Icarus honors Greece's fallen flyers.

Around 100,000 bodies are buried below the medieval headstones, many of which mark graves with multiple bodies stacked up to 12 deep.

Synagogue built from the stones of Solomon's temple contains the golem of Prague.

A surreal statue honoring Prague's favorite literary son.

The slender brass strip in Prague's Old Town Square was used to tell time from 1652 to 1918.

Macabre astrological automaton clock dating to the late 1400s.

This spooky statue sits outside a famous Prague theater.

One of the greatest collections of coins in the world is housed in the former mansion of an archeological pioneer.

A historic building houses one of the most important archaeological institutes in Europe.

A 2,000-year-old computer demonstrates remarkable engineering and astronomical precision.

A crushed gate and giant bronze head serve as a reminder of Greece's fight for freedom.

A tiny Greek Orthodox church from the Ottoman era hides on a busy city street.

This gem is often wrongly overshadowed by the larger, newer Metropolis church in Athens.

An ancient octagonal weather station named for the eight Greek gods of wind.

A small museum dedicated to the history and design of German packaging.

A larger-than-life monument to the inventor of the Bunsen burner.

It's good luck to be mocked by this monkey.

Sitting in the basement of a castle, the largest wine barrel in the world is bigger than most apartments.

Built to test magnetically levitated elevators, the tower also boasts Germany's highest visitor platform.

The world's tallest church tower reveals a spectacular view to anyone up to the task of climbing the daunting staircase.

Albert Einstein's head sticks out of a snail shell stacked on a rocket in this truly bizarre monument to the scientist.

The name doubles as an appropriate adjective for this small ossuary.

A whimsical art tower at a Bavarian brewery includes a grotto for its mythical beer-brewing dwarves.