Aerial Perspectives – volunteers off to a flying start

Published: 3rd March, 2022

Volunteers for the Aerial Perspectives theme of the Broads Hidden Heritage project, co-ordinated by Norfolk County Council, have taken to the skies from their own homes in the search for new archaeological sites in the Broads.

The project has recruited twenty-six volunteers following a series of free online induction workshops hosted by Sophie Tremlett (Senior Air Photo Interpreter). There was no obligation to volunteer following the events which sixty-two people took the opportunity to attend. Participants were introduced to aerial photographs and lidar, aerial mapping and the aerial archaeology of the Broads.

Each registered volunteer is working on their own 1km square (or squares) of the Broads landscape. Using the skills and techniques covered during the induction, and armed with a manual and recording form, they are trying to spot archaeology and distinguish between man-made and natural, or ancient and modern features. They have been provided with maps, an aerial photograph and lidar extracts for their area, as well as links to other optional sources. So far, twenty-five 1km grid squares have been completed, and a further twenty-five are in progress.

Figure 1. Lidar visualisations © Norfolk County Council. Source: National LIDAR Programme TG50NW Environment Agency 26-MAR-2018 © Environment Agency copyright and/or database right 2021. All rights reserved.

All work submitted by the volunteers is being checked by a professional aerial archaeologist, and feedback provided about what was found. Regular online catch-up sessions allow volunteers to ask questions, exchange tips and keep up to date with the latest discoveries. Any new archaeological information is being added to the relevant county Historic Environment Record, so that it is available for future researchers, and to help ensure that these important sites are considered in future management decisions.

Figure 2. Aerial photograph: Google Earth 02-JUL-2006 accessed 27-SEP-2021 © Infoterra Ltd & Bluesky.

With up to a quarter of the grid squares checked and validated, the project has already identified twenty-four new archaeological sites and uncovered new information about a further sixteen previously recorded sites. The sites encountered include new ring ditches at Beighton and Halvergate (Fig.2). Some probably mark the site of former Bronze Age round barrows (burial mounds). Numerous round barrows once dotted the Broads uplands and would have been significant markers in the landscape for many centuries or even millennia! Other marks could indicate the site of roundhouses, that once formed part of a prehistoric settlement.

Figure 3. Aerial photograph: Google Earth 02-JUL-2006 accessed 27-SEP-2021 © Infoterra Ltd & Bluesky.

Extensive areas of field systems and trackways have been seen on the aerial photographs. Some of these are probably remnants of the medieval and post medieval landscape, but others are likely to be considerably earlier, and perhaps of Iron Age or Roman date. They attest to the long occupation of the Broadland landscape by human populations, and the intensive exploitation of the light fertile soils of the Broads uplands in the prehistoric and Roman periods.

The line of a probably medieval or post medieval road at Beighton is visible as a cropmark on some aerial photographs e.g. (Fig. 3). Crops over the buried roadside ditches have grown taller and thicker, and are taking longer to ripen, than the surrounding crop. Adjoining field boundaries and possible traces of an earlier field system are also visible.

Figure 4. Point cloud model created using Quick Terrain Reader © Norfolk County Council. Source: National LIDAR Programme TG30SE Environment Agency 1m POINT CLOUD 26-MAR-2018 © Environment Agency copyright and/or database right 2021. All rights reserved.

At Langley with Hardley several interesting earthworks have been newly identified on visualised lidar data (Fig. 4). Lidar – airborne laser scanning – can be used to create a 3-D image of the ground surface, allowing even subtle earthworks to be seen more clearly. The lidar visualisation has been created using Environment Agency point cloud data. High points in the model, like the tops of trees, are coloured red, while low points are dark blue.

At Langley, two previously unknown, roadside building plots or platforms are visible as earthworks (on the left of Fig. 4, next to the road). These lay at the edge of what was once common land, on the edge of Langley Marsh. They are likely to be of medieval to post medieval date; roadside properties of this type appear to have been a relatively common feature of rural medieval and post medieval Norfolk.

Also at Langley, a range of rather more enigmatic linear banks and ditches extend across the marsh. Some of these have the appearance of former drains and one substantial feature is perhaps a drainage bank or causeway (in the centre of Fig. 4). It is possible that the medieval abbey of Langley, which lies a short distance to the southeast, played some part in the creation of these features.

The work of the Aerial Perspectives volunteers continues to reveal more about the hidden heritage of the Broads.