This charming old building's loose connection with the Scottish Reformer is what saved it from demolition after it split apart.

These steps offer a breathtaking view of one of Europe's most besieged fortresses.

Now home to a drinking establishment, this building has a macabre history.

Remnants of the 16th-century defensive wall still stand unassumingly within Edinburgh.

The tomb of one of Scotland's bloody historic villains is a magnet for bumbling desecrators.

The most loyal of little dogs, or a Victorian era publicity stunt?

Protecting the dead from opportunistic body snatchers.

This obscure walkway links Edinburgh’s Old Town with one of the city's prime vantage points.

A beautiful Greco-Roman structure houses a well once believed to have healing powers.

A labyrinthine network of chambers with a storied past hides below Edinburgh's South Bridge.

A sweet symbol marks the place where torturous executions were once carried out.

360° views of the city plus five floors of optical illusions and hands-on science.

17th century streets hidden under Edinburgh were once a breeding ground for the black death.

Catacombs turned marketplace.

The medieval "dragon" on an Austrian city's coat-of-arms comes to life in a fountain.

This spire on an Austrian mountain is wrapped around a long spiral slide and has the world's tallest wooden observation deck.

A museum dedicated to a secret military hospital hidden beneath a castle in Budapest.

From Austrians to Nazis to Soviets, this historic Budapest fortress has a history as complex as the city itself.

Built in 1870 at the bridge that connected Buda and Pest, this spectacular incline railway was almost lost forever during World War II.

This Hungarian castle was built out of cardboard and wood until it proved so popular that it got upgraded to stone.

An extensive collection of reliquaries containing the bones of saints housed in the largest Catholic church in Venice.

This Roman statue is missing a limb from when the Venetians stole it from Constantinople during the Crusades.

Two stone columns flank the grand Venice square, but there were supposed to be three.

Go inside to really appreciate this 500-year-old technological masterpiece.