More than 100 examples are recorded in France and 70 in Southern England and Wales, while further sites are known in Scandinavia, Belgium, Germany, Italy, Ireland and Slovakia.
They should not be confused with segmented, or causewayed ring ditches, which are smaller and are thought to relate only to funerary activity, or with hillforts, which appeared later and had a definite defensive function.
The presence of human remains in the banks and ditches of the enclosures has been seen as an attempt by the builders to connect their ancestors with the land and thus begin to anchor themselves to specific areas.
Environmental archaeology suggests that the European landscape was heavily forested when the enclosures were built; they were rare clearings in the woodland that were used for various social and economic activities.
Animal remains (especially cattle bone), domestic waste and pottery have been found at the sites, however there has been limited evidence of any structures.
The sequential addition of second, third and fourth circuits of banks and ditches may have come about through growing populations adding to the significance of their peoples' monument over time.
French examples begin to demonstrate elaborate horn-shaped entrances which are interpreted as being designed to impress from afar rather than serve any practical purpose.