Prehistoric Dartmoor Walks, walking the Stone Rows and Stone Circles of Dartmoor
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Dartmoor Resource: Prehistoric Dartmoor Walks GPS Datasets

Prehistoric Dartmoor Walks GPS Datasets - Update December 2025

The GPS datasets available on this page are snapshots taken of the information stored in the Prehistoric Dartmoor Walks database. The listings include all known visible stone circles, stone rows and cists and cairns. Sites that have been destroyed, or are no longer visible or are very doubtful are generally excluded from this dataset but are available on request. Data for round houses is not included here but is available on request. The website did not originally attempt to cover all prehistoric sites but significant work has been done on this in recent years and the listings are now much more complete and incorporates all major listings previously published from Grinsell and Jeremy Butler to the Historic Environment Records. Datasets managed by other people, such as the HER data will change and evolve over time and this author suggests any researchers need to double check the HER as the data here was based on a snapshot a few years ago.

Below are listed annual, or twice annual, datasets in YYMM format (by Year and Month). The data has come together through years of research although much of it is taken from published books and papers. Many of the grid references are checked against Google satellite or by site visit with a Garmin GPS device. These will be accurate to within 3 to 5 metres. The figures taken from various academic texts will at best be accurate to only within 10 meters and quite often to only 100m. Finally, most of these sites are within the Dartmoor National Park and as such are accessible, unless they are on firing ranges in which case you need to check whether firing is taking place. A few however are on private land and no right of access is implied by their inclusion in these listings - check the Dartmoor OL 28 Explorer Map for access rights.

A snapsot of the data is availble from 2017 as a google map:

Prehistoric Dartmoor Map

Guide to naming and suffixes

We use the convention of naming versions as YYMM. All of the data will appear in your GPS device or in MapSource with a name which is restricted to 14 characters. Each name will have a two character suffix such as "SR:" for example "SR:ShaughMoor" means Shaugh Moor Stone Row. The third character indicates the stus of the site "?" means questionable and "x" means probably destroyed or not in existence. These suffixes are:

The third character indicates the status of the site ":" means known and exists. "?" means questionable and "x" means probably destroyed or not in existence. Examples of these suffixes are:

As of July 2022 the third character has been changed to also indicate whether the site is recorded in the database with a photo and presumed accurate grid reference. This is to help with field visits to know when sites are already recorded with details and how accurate they might be.

Datasets created Dec 2025

The Dec 2025 dataset builds on previous datasets with the latest additions and refinements. It includes Greeve's "sacred pools" and a list of Iron Age Devon Hillforts which covers locations outside of Dartmoor. Since May 2024 a further 210 site records have had photos added and most will have had the grid reference updated at the same time.

This list includes 2039 sites and excludes most round houses which are approx another 4000 records which is beyond the capability of the authors' Garmin! Older datasets are no longer listed here except old listings by site type.

Datasets created May 2024

The May 2024 dataset builds on previous datasets with the latest additions and refinements. It also includes for the first time a list of Iron Age Devon Hillforts which covers locations outside of Dartmoor.

This list includes 1875 sites and excludes most round houses which are approx another 4000 records which is beyond the capability of the authors Garmin! Older datasets are no longer listed here except old listings by site type.

Data sets suitable for older garmin devices

If your device can cope with 2039 entries then use the Dec 2025 data above otherwise if you want smaller datasets these older versions are available.

Stone Circles dataset

Last updated in May 2019

Stone Rows dataset

Last updated in May 2019

Cists dataset

Last updated in August 2017

A word on accuracy of data

There is a hierarchy of grid references in the database as follows:

As sites are visited the grid references are confirmed or updated. If a feature can be seen in Google Satellite, then the centre of the object is most accurately determined by using the Lat & Lon of that point. Typically, accurate to within 3 metres or so. A hand-held Garmin is slightly less accurate to around 2-4 metres. For all other sites the grid references are taken from the HER or the literature (often the same thing). The more modern HER records will have 10-digit grid references where the reporter has been using a Garmin GPS device. Those grid references are unconfirmed by this author but likely to be fairly accurate. Some however have 8 or even 6-digit grid references.

The Butler records originally had 8-digit grid references (theoretically accurate to nearest 10 metres at best but often to around 20-40 metres) although if the feature has been located on Google satellite or by the author in the field then a more accurate grid reference is given. The older records from before the 1990s such as the Grinsell cairn listings are often only 6-digit which is accurate at best to the nearest 100 metres. If a site has a photo in the listings, then it has been located by the author and the grid reference recorded accurately using a Garmin.

Of course, point data does not match structures that are linear such as stone rows. In that case usually one end of the row has been used. For stone circles the centre of the circle is used and as most can be seen on Google satellite the data is highly accurate. For large features such as hillforts or settlements the precise centred grid reference is less relevant and a grid reference that looks approximately centred on the feature is used.

Page last updated 25/12/23