Scotland’s largest archaeological mapping project

George Geddes dives into the history of Scotland’s largest archaeological mapping project, how it happened and the recent efforts taken to make all of this data available digitally for the first time.

In 1999, a comprehensive ten-year archaeological mapping project in Scotland came to an end. The result was a record of more than 6,000 sites across 35 different areas, covering some 1,500km².

This dataset was at that time, and possibly still is, the largest and most detailed archaeological mapping project that has ever been undertaken in Scotland.

Why was the project needed?

In this age of climate-change, development and reforestation, Scotland’s heritage can seem increasingly challenged by both the existential and the mundane. Back in the late 1980s the situation was surprisingly similar. A huge increase in forecasted tree-planting posed a risk of changing, damaging, or in some cases destroying sites that had not yet been recorded.

While forest expansion is more commonly undertaken now in a way that balances the needs of cultural and natural heritage with the benefits of woodland creation, the situation in the late 1980s wasn’t as considerate. Ploughing, mounding, drainage and road works had damaged some archaeological sites.

Plus, given that roughly the area of Edinburgh was to be planted each year, the changes to Scotland’s landscapes could be significant. Then, as now, the baseline survey data (the what and where if you like) was crucial for decision making.

Historic Scotland and the Royal Commission on the Ancient and Historical Monuments of Scotland worked closely together to provide a response for the known and unrecorded sites that may be impacted by afforestation (the process of planting trees on land that was not previously forested).

In 1989, a new programme of archaeological survey, the Afforestable Land Survey, was established. This was to ‘rescue’ as much information as possible in areas where afforestation was likely, clarifying the location, the classification and the extent of each archaeological feature. Both the Forestry Commission and Council archaeologists were key consultees, ensuring that national bodies worked to support their regional colleagues and shared collective aims.

The bigger picture

The emphasis from the start was to record archaeological landscapes, seeing traditional archaeological monuments such as forts and burial cairns not just as nodal points, but as interconnected parts of multi-period landscapes.

New surveyors trained in the latest techniques were allied to old hands, marrying experience and efficiency. An inclusive approach to archaeology gathered data on everything predating the 1st edition of the OS maps (1843-1882) and more recent material on a selective basis. This provided a broader and more holistic view of the past, helping to clarify which sites were of greater cultural significance. Where justified by the archaeological potential, more detailed survey was also undertaken of smaller areas of landscape and of individual sites.  

The last ALS project, a survey of Menstrie Glen in the Ochils, recorded a remarkably well-preserved pre-18th century farming landscape using Total Station survey and aerial photographs. The characteristics of each structure were recorded in a database that was used to produce summary site descriptions. These, together with the survey data and photographs, form a project archive that is available for public consultation and use.

Almost 25 years later the publication is still one of the best examples of the integration of archaeological landscape recording with a remarkably rich historical record of rare detail, much of which was highlighted by historian John G Harrison. Over the last decade the Glen has been progressively afforested – highlighting the value of the survey and analysis for an area that has now been profoundly altered.

Going digital

The team of archaeologists and surveyors who did this work were all keen to try out novel technology that might improve results and particularly efficiency. They trialed field computers, highly accurate Total Station and GPS survey technology, born digital survey methods and photogrammetry for mapping (including geo-referencing RAF air photographs). Though not all tests were successful at the time, all these approaches are now bread-and-butter techniques – a demonstration of how far archaeological survey has come.  

Getting it out there

A recent project has sought to make all of this data available digitally for the first time, improving accessibility and leveraging the resource investment of the past into the future. In particular, much of the information on the ‘why, where and what’ of the survey data was not accessible, meaning that users were not as well-informed about the character of the resulting information as they could be.

Now this project is finished, each of the 6,000 site records on trove.scot has been updated with modern spatial data (updated position and area) and a check of classification and period. The survey results have been archived to modern professional standards, making the primary and secondary data available to future users. This data, held in GIS and database formats, can now be mined for additional value in a way impossible in the 1990s.

This improved accessibility, combined with clearer explanations of how the survey was undertaken, has increased the value to heritage managers, researchers and consultants for many years to come.