They started their work in summer.
They prepared road for transportation. They needed a clean and glade road without stones and other irregularities. (No.4 on picture)
Perhaps they cut the topsoil and covered the road with clay. (No.3 on the picture)
On each side they made curbs ( 5-10 cm). (No.2 on the picture)
They used clay because they wanted to hold water inside the road.
In autumn rains filled road with water. It looked like a big puddle. (No.5 on the picture)
In winter road froze. Then they got a smooth ice skating rink slightly wider than a megalith.
Megaliths (No.11) were transported in winter.
Mechanism and vehicles for transportation were prepared in summer.
Mechanism consisted of three parts.