The Altar Stone is one of the most unique stones in
Stonehenge. It is a 5 meter (16 foot) block of dressed green sandstone
located near the center, embeddded 15 feet within the great central
sarsen trilithon. All of the other stones in Stonehenge are either
composed of sarsen or bluestone.
The Slaughter Stone is another unique stone.
It is one of two stones at the entraceway, the Slaughter Stone being
the more easterly of the two. It is in fact 21 feet long, but it is
sunken so deep that only the upper surface shows. It was originally
The Heel Stone is a stone which is not located
in the main circle. The Heel Stone, formerly Friar's Heel, is the Anglicized corruption of the ancient
Welsh "Freya Sul". Sul (pronounced "seal" in old and modern Welsh) means Sun Day.
Four station stones lie just inside the embankment,
approximately in line with the Aubrey Holes
. They were erected during Phase III. Lines connecting the stones
opposite each other will intersect at the very center of the monument
at an angle of 45 degrees and are symmetrical with respect to the main
The Aubrey Holes, named for John
Aubrey, circle around the "Y" and "Z" holes. They were first
noticed by Aubrey, and thus carry his name. They consist of small,
barely visible, manmade cavities filled with rubble.
Thirty "y" holes and 29 "z" holes circle around
Stonehenge. They are concentric circular holes. The Y holes lie 11
meters (36.1 ft) outside the Sarsen Circle, and the Z holes lie 3.7
meters (12.1 ft) outside the Sarsen circle.