A giant gun barrel in Barbados that once hoped to shoot outer space with science.

This full-sized orange tree lives suspended in mid-air above the streets of Jaffa.

An abandoned tank sits in an empty London lot as a symbolic middle finger to local city planners.

These massive concrete balls were used to mine gold in Virginia.

This small shop walked so America could run on Dunkin'.

This ancient walled garden turns fog into food.

A disconnected rotary phone for "calling" lost loved ones offered a unique way of dealing with grief in disaster-stricken Japan.

An eerie reminder to the horrors of World War II.

The first geometric self-supporting spiral stairs in Britain are a truly beautiful sight.

Railroad officials in the early 1900s sought to spare travelers the sight of Roman soldiers’ private parts.

The enormous 250-room Vanderbilt mansion conceals hidden doors and secret passageways.

Monty Python fans will recognize this abandoned mine as the Cave of the Killer Rabbit of Caerbannog.

Some believe that this ancient mural depicts technology far ahead of its time, but in reality it's nothing quite out of place.

Built in a perfect square, this archaeological site is one of the largest and best preserved ancient fortifications in India.

A 605-page Quran penned in the blood of a dictator is locked away in a mosque.

The floor of this spectacular Baroque sanctuary is covered in memento mori.

This abstract sculpture is rumored to cast a hammer-and-sickle shadow once a year.

This grisly exhibit houses skeletons and weapons from a devastating 14th-century clash.

This curious sculpture represents the perseverance needed to take to the skies.

Mysterious face-like images that appeared within an Andalusian house are surrounded by legends of the paranormal.

This exhibit pays tribute to the “humble tinkerer” who invented the implantable pacemaker.

The strikingly modern structure stands out among the brick buildings speckling the Harvard Business School's campus.

Psychoanalyst Carl Jung reported a paranormal experience after visiting this mosaic-lined Roman baptistry.

High atop the Eiffel Tower is a small apartment built exclusively to entertain the science elite and make the rest of Paris jealous.