This expansive bridge in the Canadian wilderness was originally just built for friends.

An operating lighthouse from the 1860s.

Hidden within the waterfront hills resides this dilapidated military stronghold.

A famous hotel houses an impression collection of mini dioramas and giant doll houses.

This historic Victorian hotel has a scandalous history of affairs and murder.

The narrowest street in Canada was once a spot for dastardly doings, now a historic piece of Chinatown.

This large, circular tomb is the final resting place of the first emperor of Rome.

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

The Pope’s secret escape route.

An unremarkable wooden wheel built into the side of one of Rome's oldest hospitals was part of a policy to reduce infant exposure.

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

Breathtaking and huge 430 year old maps of Italy.

One of the world's heaviest musical instruments towers within a popular urban park.

A monument to the three wars that led to German unification towers within a Berlin traffic circle.

An "inside out" building in the historical center of Paris, featuring Europe’s largest modern art museum.

This iconic Parisian bookstore doubles as the "Tumbleweed Hotel" for traveling writers.

A dead saint, a deadly poison, and a mysterious holy ooze.

According to tradition this is the oldest church in Venice, but its actual age is a mystery.

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

The Greek island's old British cemetery feels like a forgotten garden.

A fountain standing as a testament to a doomed alliance.

A marvel of Byzantine engineering under the streets of Istanbul.

Legend says if you stick your thumb in the hole and it gets wet your wish will be granted.

This column celebrates Rome's victory over the Goths, and may be the oldest Roman monument in Istanbul.