A bust of Franz Kafka spins in pieces, reflecting the writer's inner torment.

Macabre astrological automaton clock dating to the late 1400s.

The only subway station in the city that still makes use of gap fillers.

Pulled from the rubble of one of the worst modern tragedies, a steel crossbeam became a symbol of hope for New Yorkers.

The most confusing clock in New York.

Slyly buy a shake in the Parker Meridien lobby.

Under a glass sidewalk lie the remains of some of Manhattan's oldest buildings.

Elevated freight railway turned wildly successful urban park.

This sculpture by artist Fritz Keonig survived the 9/11 attacks and now stands as a monument to the victims.

This fortress dates back to the 6th century and is also the site of a controversial abandoned restoration project.

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

These ancient ruins hide in plain sight next to a dessert shop.

Scars of this building's past life as a violent prison still cover its walls.

This ancient Greek place of assembly and marketplace is being revealed layer by layer below the modern Athens cityscape.

Cold war icon and onetime "hole" in the iron curtain.

On the Spree bank, discover one of the last reminders of a symbolic wall that divided, and was torn down by the people.

A fascinating insight into daily life in the Eastern Bloc.

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

Fortune tellers, snake charmers, poets, and storytellers all gather on this historic square in Morocco.

This 1,300-year-old marker is one of the finest and most complete early Christian crosses in Scotland.

In Twickenham sits a small whitewashed castle that inspired Mary Shelley's 'Frankenstein.'

This stretch of beach is the site of a prime watering hole and a primate watchtower.

This ancient oak tree sheltered accused "witches" in the 17th century.

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