This material appears to have been brought from a variety of sources, much of it probably being generated outside the henge during the course of domestic routine.
The inside of the henge was lowered, with the material produced piled onto the banks.
The henge is surrounded by two ditches and a bank.
Archaeological excavation of the central henge has taken place.
The henge contains 24 pillars and is 30 m in diameter and about 4 m high.
The henge portion has given its name to a class of monuments known as henges.
The pillars are capped with lintels, completing the circle, and a 5 m-tall obelisk marks the center of the henge.
Although the henge is not perfectly circular, it has a diameter of about 420m yd across.
