These wire animal sculptures commemorate the exotic inhabitants that once called the Tower of London home.

This bookstore serves recipes from the cookbooks on sale.

Catacombs turned marketplace.

An eccentric 18th century naval officer built a ship's quarterdeck on his roof, the inspiration for Mary Poppins's "Admiral Boom."

A historic arboretum and non-conformist, non-denominational park cemetery.

You can still see bits of the camouflage used to hide this Art Deco building from bombers during World War II.

An archway adorned with vulnerable flora and fauna.

Giant, friendly pelicans in Central London, the most unlikely of places.

Historic fortifications form the boundary of Vatican City, but it’s not entirely surrounded by walls.

The first statue to be added to Saint Peter's Square in over 350 years is an ode to migrants and refugees around the world.

Ancient ruins hidden underneath a modern luxury hotel.

Legend has it that this bronze orb, which sat atop an ancient Egyptian obelisk, once held the ashes of Julius Caesar.

Inside this McDonald's you can dine on your Big Mac and fries next to a 2,500-year-old Roman wall.

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

Charles Dickens was not a fan of the ghastly wall dressings in this 6th century church.

This small Roman arch was transformed into a dwelling by the founder of the Trinitarian Order.

The ruins of the largest gladiatorial school in Rome are largely hidden under modern streets.

This subterranean shrine beneath a bike rental store celebrates the iconic Italian scooter.

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

A statue representing a lost Roman profession that was vandalized for centuries.

A forgotten "city of water" underneath the famous Trevi district.

This former Roman Catholic Church still contains the embalmed hearts and organs of 22 popes.

This hidden Art Nouveau courtyard is an opulent feast for the eyes.

The remains of this 2nd-century Roman temple are incorporated into a modern building.