How many sarsen stones form the outer circle of Stonehenge? The answer is 30. These enormous stones make up Stonehenge’s principal outer ring, erected during a major building phase between about 2600 and 2400 BC.
The sarsens were transported from West Woods in Wiltshire, roughly 25 kilometres north of Stonehenge. Each standing stone was shaped with mortise-and-tenon joints, while the lintels above them used tongue-and-groove joints—techniques more commonly associated with woodworking.
The circle was designed to appear almost perfectly continuous from ground level. The standing stones average about 4.1 metres in visible height and weigh approximately 26 tonnes each. A complete outer ring required 30 uprights and 30 lintels, although some stones have fallen or disappeared.
A common mix-up is confusing the outer sarsen circle with the five inner trilithons, which form a horseshoe of 10 upright stones and five lintels. Stonehenge also contains smaller bluestones and several prehistoric arrangements of pits, so the total number of stones at the monument is far greater than 30.