Stonehenge

Stonehenge, on Salisbury plain in England is one of the most recognizable monuments of the Neolithic world and one of the most popular, with over one million visitors a year. People come to see Stonehenge because it is so impossibly big and so impossibly old.

In fact, what we see today is the result of at least three phases of construction, although there is still a lot of controversy among archaeologists about exactly how and when these phases occurred. 

It is generally agreed that the first phase of construction at Stonehenge occurred around 3100 BCE when a great circular ditch about six feet deep was dug with a bank of dirt within it about 360 feet in diameter, with a large entrance to the northeast and a smaller one to the south. This circular ditch and bank together is called a henge.

The lintel stones also curve slightly to echo the circular outer henge. The stones in the horseshoe of trilithons are arranged by size; the smallest pair of trilithons are around 20 feet tall, the next pair a little higher and the largest, single trilithon in the southwest corner would have been 24 feet tall. 

This effect creates a kind of pull inward to the monument and dramatizes the outward Northeast facing of the horseshoe.