Cropmarks are imprints of human activity.
Where settlements of people have dug trenches, engaged in funerary practices, deposited materials or marked out roads, among other things, the condition of the land is affected. This in turn affects how crops grow on that land centuries later. These patterns in the colour and depth of the crops can sometimes only be observed from the air, helping us to identify areas of archaeological importance.
Our flying archaeologists have been photographing the changing landscape for over 50 years. Since the 1990s, by analysing new and archive aerial photographs, 122,000 new archaeological sites have been discovered.
Here we take a look at just 5 examples of finds from the air:
1. A Neolithic causewayed enclosure on Aughertree Fell in Cumbria
Causewayed enclosures represent the earliest known examples of the enclosure of open space. The construction of an artificial boundary around an area creates a distinction between ‘inside’ and ‘outside’, private and public, human and wild. They date to the early Neolithic (4,000BC – 3,300 BC), which also saw the introduction of agriculture and domestic animals, manufacture of pottery and the first mining of flint.
2.The distinctive elongated pits of a Neolithic enclosure in Cambridgeshire
Causewayed enclosures usually contain a sparse scatter of pits and post-holes. Early interpretations compared them to fairgrounds: a place for dispersed social groups to gather and engage in communal activities like feasting, rituals and crafts.
3. Cropmarks of an Iron age Banjo enclosure, Rollright, Oxfordshire
Banjo enclosures can be identified by a single entrance or passageway – the funnelled approach giving the impression of a banjo or frying pan. They are perhaps the most distinctive types of prehistoric enclosure known in the British landscape. Recent studies of banjo enclosures suggest that most, if not all, were settlement sites, perhaps of high status.
4. Bronze Age barrow cemetery in Fittleworth, West Sussex
This photograph taken in 2015 depicts the cropmarks of five, possibly six, circular buried ditches, which would have once surrounded the mounds of Bronze Age barrows close to the river Rother.
Barrows are mounds of earth or stone surrounded by a ring ditch from which the earth and stone for the mound was dug. They are characteristic of the period from around from about 5,800 until 3,400 years ago and were mainly burial places, but were also used by the living to carry out ceremonies.
5. Late medieval farmstead in Lavenham, Suffolk
This 2015 aerial photograph shows the buried remains of a late medieval farmstead revealed as cropmarks. You can see some of the farm’s field boundaries and a trackway which linked this farm to its neighbours. Farmsteads are a common ancient monument type and provide important information on regional and national settlement patterns – reminders of the generations of families who lived and worked the land here.
Written by Marina Nenadic, Marketing Executive at Historic England