The highest cold-water geyser in the world.

Colorado's only true geyser is hidden within the San Juan National Forest.

Brush shoulders with animatronic Arab leaders made of silicone.

Last remaining nuclear missile base in Ukraine.

The world's only complete colossal squid specimen is on display at the Te Papa Museum.

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

A Nesting Doll of Churches.

Its interior is adorned with some of the best examples of early Christian mosaics.

This Roman arch marks the location of an ancient gate at one of the Seven Hills of Rome.

An enigmatic modern marker left next to a historic Roman site.

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

A massive marble foot is tucked away in a small alley near the Pantheon.

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

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

This park on the outskirts of Rome boasts two ancient Roman aqueducts and a medieval tower.

This ancient trail climbs the mountain where a Latin League cult worshipped Jupiter, its main deity.

A detailed pachyderm supports Rome's smallest Egyptian obelisk.

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

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

Roman-era ships unearthed...

Gods clash with machines in a power plant regenerated as a museum.

This historic recreationist school churns out warriors that may very well have had a fighting chance in Rome's pits of the day.

A magnificent waterfall is also home to the remains of a Roman hydraulic engineering system.

The "Greatest Sewer" of ancient Rome is one of the oldest sewer systems in the world, and is still in use.