London's amazing modernist public square that never was.

Kings Cross Station pays tribute to its role in Britain's best-selling book series.

This 1920s Dutch barge is now a floating bookstore.

Catacombs turned marketplace.

This sculpture encompasses the emotion of rail travel.

A king's pet, a pope's gift, an artist's inspiration, and a tragic shipwreck.

Portugal's National Pantheon has a history of curses, collapses and financial problems.

This unique architectural wonder is also tied to one of the 20th-century's most renowned writers.

This Industrial Age architectural and engineering gem helps visitors and residents alike traverse Lisbon, “The City of Seven Hills.”

Legacy of the earthquake that nearly wiped Lisbon off the face of the Earth.

This once-forgotten oasis in the middle of Lisbon was first created over a century ago quite by accident.

One man's remarkable private collection of art from around the world.

These hut foundations are believed to be the residence of Romulus, founder of Rome.

A mysterious chasm in the heart of the ancient Roman Forum, the Lacus Curtius was once believed to be a gateway to hell.

An ancient Roman temple first dedicated to an emperor's wife is now a church.

A 15th-century monumental Latin inscription on this house celebrates Lorenzo Manilio's love for Rome.

This ancient Roman prison is decorated with an upside-down cross not as blasphemy but as saintly tribute.

This ancient market is often referred to as the oldest shopping mall in the world.

This ritzy Italian market is built around a statue of an unforgiven heretic who was burned for his belief in an endless universe.

This hidden alley near the location of Rome's first theater was the site of a curious miracle.

In Rome’s Jewish ghetto, a 200-year-old bakery still makes the neighborhood’s historic sweets.

Romans decided this 16th-century "talking statue" was so ugly, they named it after a primate.

This hydrochronometer was invented by a Dominican monk and is a prime feature in this garden.

A sculpture serving as an homage to Pope John Paul II.