Stonehenge

Stonehenge is a massive neolithic monument in the county of Wiltshire, England, consisting of large stone columns arranged in a circular pattern. Built by the ancient Britons around 2500 BC, the monument's original purpose has been lost to modern knowledge. It has been theorized that Stonehenge originally served either a religious or a scientific function.

Stonehenge in "The Horse of Bronze"
The Lapiths built Stonehenge on the Tin Isle. Cheiron found the structure impressive in the extreme and asked Geraint about its origins. He expected to hear that the mans had been ordered to build it by their gods. Instead Geraint informed Cheiron that they had built it to gain understanding of the physical universe through scientific inquiry, a concept which Cheiron had difficulty understanding because he had never encountered it in a mortal species before. This added to his belief in the inherent superiority of mans to other beings.