Francis Pryor at The London Magazine:
The term ritual landscape is used to describe concentrations of funerary and ceremonial monuments that were constructed in the Neolithic (4000- 2500 BC) and Early Bronze Age (2500-1500 BC). So what were they? Many grew up around the two earliest classes of Neolithic communal monuments, known as long barrows and causewayed enclosures. The construction of the latter must have taken much labour. Essentially they consist of one or more ditches surrounding an irregular, but more-or-less oval, or circular, area. The ditches are dug in variable lengths, maybe ten or twenty metres long, each one of which is separated from the next, by a gap, or causeway. The banks of upcast from the ditches tend to be irregular, but are often placed on the internal side of the ditch.
In the mid-1980s I was able to excavate an exceptionally well-preserved causewayed enclosure at Etton, in the Welland Valley on the western Fen margins, near Peterborough. The ditch was waterlogged and preserved wood, bark and other organic remains – such as the earliest piece of string (made from ax), yet found in Britain. Close examination revealed that the ditch had been dug and then immediately filled with offerings, which were placed in discrete heaps. These offerings consisted of human skulls, or inverted pots, whose round bases closely resembled skulls.
more here.