A labyrinth of ancient tunnels hidden below the city holds the ruins of 2,500 years of history.

The castle that provided the setting for much of 'Monty Python and the Holy Grail' is now a pilgrimage site for fans.

An unpaid bill, a stolen stone, and a famous fashion designer rest peacefully alongside a heroine of Highlands history.

The ruins of this magnificent Scottish castle blend both Gothic and Renaissance architectural styles.

It took 40 years to build this Eden-like garden in Marrakech, later restored by Yves Saint-Laurent.

The oldest operating pharmacy in the world features 800-year-old recipes.

The only remaining arch of the oldest stone bridge in Rome stands in the middle of the Tiber.

Next to the Leaning Tower of Pisa is a cemetery home to ancient sarcophagi and disturbing murals.

A deep mark on the remains of a Roman temple, believed to be left by a legendary warrior.

A master of trompe-l'oeil creates a stunning, tourist-fooling dome out of a flat ceiling.

The yawning maw of this pagan visage is said to bite off the hands of liars.

If you look closely at the oldest bridge in Paris, you might notice hundreds of ugly faces leering from its sides.

Designed to illustrate two parts of the human psyche.

The first woman in America to receive a medical degree.

Built in the 16th century, the tower is now in ruins.

One of only three examples of a stained glass window manufactured by the Tiffany Company in Scotland.

On the outskirts of Edinburgh, a trio of topiary created by one man over the course of more than 20 years.

In the 18th century, the Earl of Buchan mapped the universe on this stone pillar.

Edinburgh’s version of the Sistine Chapel is this former church, with an interior covered in paintings done by one woman over the course of nearly a decade.

This small memorial honors a ferocious feline and local hero.

The unconventional Scottish soccer coach required players to wear a collar, tie, and bowler hat for matches.

This bronze cat looks out over the Linlithgow Canal.

This unassuming stone is possibly the oldest Scottish memorial to the 13th-century knight.

This museum offers a glimpse into early 20th-century Glasgow life.