The Aubrey Holes no longer held posts but were partially filled, some with cremation deposits added to the fill. The numerous post holes indicate timber structures but no clear patterns or configurations are discernible that would suggest their shape, form, or function. They originally supported sarsen lintels forming a continuous circle around the top. Each lintel block has been shaped to the curve of the circle. The Sarsen Circle with its lintels is perhaps the most remarkable feature of Stonehenge in terms of design, precision stonework, and engineering.
Sarsen stones are hard-grained sandstone with with a silaceous cement.
They were probably brought to the site from the Marlborough Downs, about 30 kilometres to the north of Stonehenge. The Trilithons are ten upright stones arranged as five freestanding pairs each with a single horizontal lintel. They were erected within the Sarsen Circle in the form of a horseshoe with the open side facing north-east towards the main entrance of the monument. Only three of the five Trilithons are now complete with their lintels. The other two both have only one standing stone with the second stone and lintel lying on the ground.