At one end the ditches terminate in a circular area some 150 feet in diameter. These ditches contained palisades, wooden fences marking the necropolises. That they were built in wood and earth implies considerable effort. Numerous large trees had to be cut down with burnished adzes, then stripped of their branches and transported. The volume of moved earth was tremendous considering that the Cerny people had no knowledge of metals and had to use the backs of animals or wooden buckets.
Different periods seem to account for the different shapes.
Long lines were characteristic of the elongated houses of the Danubians, predecessors of the Cerny inhabitants, who settled the region in the second half of the sixth millennium. At Balloy, the plan of certain Cerny necropolises perfectly copies the foundations of houses abandoned for ages that belonged to the Danubians. These houses, made of wood and straw, are well known and easily spotted by their deep postholes. The ditch was possibly used as a tomb, though no skeletons were recovered. Several structures contain one or more tombs, while others have none.