ORNKEY ISLANDS, Scotland (KFOR/Storyful) — Archaeologists have discovered an “incredibly rare” ancient tomb in Scotland’s Orkney islands that dates back 5,000 years, and contains the remains of at least 14 men, women and children, along with other artifacts.

National Museums Scotland released the video at the top of this story, showing the excavation in progress.

Officials call the tomb a “pinnacle of engineering” during the Neolithic period in northern Britain, which was nearly lost forever.

The “tomb was buried beneath a pasture field as it was largely destroyed in the late 18th or early 19th century to supply building stone for a nearby farmhouse,” according to NMS.

“Orkney is exceptionally rich in archaeology, but we never expected to find a tomb of this size in a such a small-scale excavation. It’s incredible to think this once impressive monument was nearly lost without record,” said Dr Hugo Anderson-Whymarkt, a lead researcher during the dig.

Students from the University of Central Lancashire also found remnants of pottery, stone tools and a bone pin.

“The preservation of so many human remains in one part of the monument is amazing, especially since the stone has been mostly robbed for building material. It is incredibly rare to find these tomb deposits, even in well-preserved chambered tombs and these remains will enable new insights into all aspects of these peoples’ lives,” said professor Vicki Cummings.

Excavation at the site will continue for further investigation.