The first stage of construction was Stonehenge 1, whose construction began around 3100 BC. The structure comprised a circular shaft, and the ditch reinforced with chalk rock. The circle had a diameter of 110 meters and two entrances: one, the larger one located to the northeast, and a smaller one facing south. Within the rampart, 56 chalk-filled pits were also excavated, the significance of which is still unknown. They were named Aubrey Holes in honor of John Aubrey, who was the first to spot and describe them during his visit to Stonehenge in 1666.
