Off the coast of Scotland, on the Isle of Arran, archaeologists have discovered a Neolithic monument that was used for ancient ceremonies and gatherings.

Archaeologists from Glasgow University and local volunteers began excavating at Drumadoon, the site of the only complete Neolithic cursus monument in the region, this past August.

A cursus is a vast rectangular enclosure believed to have been constructed for processions, ceremonies, and gatherings. These structures are among the earliest and largest constructions in the isles. They date to between 4,000 and 3,000 BCE, and range in size, from 656 feet to 6 miles long.

At more than one half-mile long, the Arran cursus is close to the standing stone circles of Machrie Moor, which was a significant ceremonial site. The cursus, however, predates the stone circles.

“It’s strategically located to take people from the coast up to the interior of the island and to showcase Macrie Moor,” Kenny Brophy, a senior lecturer in archaeology at Glasgow University and a cursus specialist, told the Guardian.

Those who erected the cursus using sticks and bone tools would have been among the first farmers in Scotland. It was likely built over the course of multiple decades by locals or visitors on pilgrimage bound by a strong religious or political belief.

Archaeologists believe the combination of ceremonial and farming landscape in the area may be part of a more extensive program.

The remains were initially found five years ago using a Lidar survey or laser-light method conducted by Historic Environment Scotland.