All the Neolithic ‘monuments’ listed were instruments for land surveying. The instruments, along with the surveying method, evolved over time to improve accuracy and to survey areas missed by the previous method.
The enclosures, cursuses, stone circles and henges, all performed the same underlying function in that they enabled new survey lines to be set out from a ‘survey station’ whose location had been previously fixed. Each new line needed to be set at a known angle relative to a line which had fixed the survey station. The monuments, built at the survey station location, enabled that. A net of survey stations was created with their locations fixed relative to one another. The land became mapped without the need for a compass.
The chronology and design of the monuments suggest that in mainland Britain there were at least four distinct phases of surveying, each demonstrating an evolution in instrument and method. Whilst each phase heralded in a change in method, there may have been transition periods where a replacing method was introduced in one part of the country whilst its predecessor was still being used elsewhere. A further complexity is that they sometimes retained, albeit with enhancements, a method from an earlier survey for a specific region.
The four phases in mainland Britain were:
Phase name Short name Approx dates in British Isles
Causewayed and Tor Enclosure survey Enclosure survey 3800-3500 BC
Cursus survey Cursus survey 3650-3300 BC
Circle, Henge and Circle-Henge survey Circle survey 3300-2600 BC
Mega-henge and mega-mound survey Mega-henge survey 2600-2350 BC