Archeologists studying aerial photography of a wheat field near Stonehenge have discovered the remains of one of the oldest architectural structures ever built. Dating back approximately 5,600 to 5,700 years, the site is believed to have a held a massive Neolithic long barrow or "house of the dead." According to excavation lead Jim Leary, it's the first time a monument of this kind has been discovered in Wiltshire in nearly half a century.

"Opportunities to fully investigate long barrows are virtually unknown in recent times, and this represents a fantastic chance to carefully excavate one using the very latest techniques and technology," he said in a statement.

A critical shift in how humans lived

The Neolithic period is extremely interesting to archaeologists because it marked a shift in humans from societies of hunters and gatherers to farming communities. Long barrows served as a place of internment for the deceased, with dozens of bodies contained in a single structure covered by dirt. Over several millennia, the structures gradually blended into the surrounding countryside, looking today like little more than natural hills in fields and forests.

You can see an example of a particular large barrow dating back to about 3,700 B.C. in the drone footage below.

Smaller, razed sites, such as the newly discovered long barrow in Wiltshire, likely were lost due to farming practices.

"This land has been plowed for millennia," Leary said in a video. "It's a very rich and fertile landscape and as a result the monuments are plowed completely flat, and all we're looking for are the features that are cut down deep into the natural ground."

How they found it

The aerial photograph that tipped off the team to the presence of an ancient structure. Note the faint outline of long barrow within the horseshoe. The aerial photograph that tipped off the team to the presence of an ancient structure. Note the faint outline of long barrow within the horseshoe. (Photo: University of Reading/Facebook)

An aerial survey revealed a rectangular structure surrounded by two large flanking ditches in the shape of a horseshoe. Leary believes the ditches produced the soil that was used to cover the building.

As they excavate more of the long barrow's footprint, the team expects to find human remains, neolithic pottery and other artifacts.

"This is an extremely exciting opportunity to dig and extremely rare type of monument. We are extraordinarily privileged and that is felt by all of the students that have that opportunity to work on the monument," Leary said. "From these excavations, we should be able to add so much more to the history of us, who we are, and where we've come from."

Michael d'Estries ( @michaeldestries ) covers science, technology, art, and the beautiful, unusual corners of our incredible world.