If geophysics is like an x-ray, then here’s why digging test pits is the archaeological equivalent of a biopsy.
Out in the West Country, right on the banks of the River Severn, lies Oldbury Camp – a rare lowland hillfort. Known locally as The Toot, its huge earthen banks are visible from the air. Over the years, bits of Roman pottery and coins have turned up, but archaeologically, it is yet to be investigated. How old is it? What was it used for? And why, unlike most other hillforts, isn’t it built on top of a hill?!
Finding out will require a full-blown excavation, but in order to do that, we’d need to dig 10 test pits across the hillfort. From each one, we’d extract a small, precise sample of the archaeology to diagnose what survives, and where, before deciding where to put full-size trenches… like the archaeological equivalent of a biopsy! We invited 20 Dirty Weekenders along to help us carry out the operation. Here’s how we did it.
First, we checked out the hillfort on Google maps
Then, we had a look at the geophysics map
And decided on the best places to dig each of our 10 ‘test pits’
Each one measured 1x1m and, with the turf stripped, we were ready to go!
Iain and Sean dug theirs right on top of the hillfort’s huge earthen ramparts
Wendy and Keith dug theirs at the bottom
Johanna and Geoffrey dug theirs in a field full of ridge and furrow marks
Mary and Sue dug theirs over a long geophysical anomaly
Juan and Barry dug theirs very quickly – already up to your arm pits? Oh my!
Janet and Kieron dug theirs very, very tidily
And George dug his wearing a woolly beard-hat (bet you want one too!)
At the end of the day, some winter lambs came to see what we were up to
Yes, this is Old-baaaaaaaaaary Camp!
Then it was time for Adam to photograph each of the test pits
So what did we actually find?
Thanks to Iain and Sean, we know how the ramparts were constructed…
And where we’re most likely to find prehistoric pottery
Justin found some too…
And so did John…
Kieron was the first to find flint
We also learned where we’re most likely to find nothing at all… Sorry Barry!
All in all it was thumbs up from Johanna
And thumbs up from Juan
And a huge big grin from Amanda, our Finds Manager!
Because now we know the best (and worst) places to put our trenches when we come back to carry out a full-scale operation (I mean excavation!) next year
We hope you’ll join us! But if you can’t wait until then, you CAN check out the 3D photogrammetry model that Adam made. You can even click on each of the test pits to take a look inside!
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