The plant

The Heel stone and the location of stones at Stonehenge are arranged according to the positions of the solstices and equinoxes. Therefore, it is often assumed that Stonehenge is a prehistoric observatory, although the exact nature of the use and importance, as the sowing and harvest the best times (see below) are still being discussed.

Description of Stones
* The altar stone is a block of 5 meters of green sandstone. All the other stones in the inner circle are blue stone (dolerite), a basaltic from the Preseli Hills in southwest Wales, which are located about 380 km. The sandstone blocks of the outer circle must have been moved on sledges pulled by an estimated 250 men, on inclines of up to 1,000 men. Alternatively, the use of draft animals is discussed.
* The altar stone is somewhat isolated from the center.
* The Heel Stone (Stone heel), also known as Friars Heel.
* Position stones

Other special features:
* The Aubrey holes
* Y and Z Holes
The plant is similar to the stone circles in the north of Scotland, known as the Ring of Brodgar.