Numberless clock creates a meal of time for the dreaded, insectile Chronophage.

An unusual artwork dedicated to a unique man that entertained people visiting Cambridge while raising money for charity.

Erected in memory of Sir Arthur Conan Doyle, who was born close to this spot, this statue commemorates the author and his famous detective.

A roadway designed for a visiting monarch.

The oldest floral clock in the world still functions today.

The site where a plot to assassinate Hitler was planned—and its conspirators were executed—is now a powerful memorial to the German resistance during World War II.

The bunker where Hitler took his own life is hidden under this deliberately ordinary parking lot.

Hidden beneath the famous St. Peter's Basilica is a veritable city of the dead that may hold the remains of St. Peter himself.

Dedicated to the European Sinti and Roma peoples murdered during the Holocaust.

A pair of stones embedded in an Edinburgh street memorialize one of the city's last public hangings.

This popular square's history as the former site of a church is right beneath your feet.

Follow the original medieval paths that wind through this intriguing section of the city.

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

Inside this building is another country within Rome, a sovereign entity without a physical territory.

Rome's first modern graffito is all that is left of a peaceful protest from the 1970s.

A small but very fascinating fountain in the center of Rome with four books and a deer carved.

This is the oldest Roman-made bridge in the city still existing in its original state.

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

A freedman baker’s lavish tomb has a relief showing various stages of Roman bread making.

A monument to a Russian cruiser near its final resting place off the Ayrshire Coast.

Legend says this cave housed a 16th-century cannibal and his family of 48.

Near this coastal cave stands a small memorial to the hermit who made it his home for three decades.

A 200-year-old collection of oddities and medical paraphernalia.

Inside this art museum resides one of Glasgow's most famous musical instruments.