Grime's Graves

 In 1995, English Heritage's Landscape Investigation Team completed the most detailed ever analysis and surface survey of the extraordinary lunar landscape of Grime's Graves, the complex of 5,000 year old Neolithic flint mines in the Norfolk Brecklands. Since then, English Heritage has commissioned a 3D laser scan of the underground shaft and galleries of Greenwell's Pit, one of the three mines that can still be entered. The excavation of the shaft in 1868-70 by Canon William Greenwell of Durham Cathedral proved for the first time that prehistoric flint mining had taken place in  Britain.

 The project has made use of the latest Cyrax 2500 laser scanner to collect millions of 3D points to accurately model the irregular, fractured surfaces of the shaft walls and side galleries. This is the first time such technology has been used to record a Neolithic flint mine. The preliminary results show an astonishing amount of detail which would otherwise be very difficult to record, from the marks left by the Neolithic miners' antler picks, to the shallow pock-marks in the gallery floors left by the flint nodules that they succeeded in prising up. It has given us a record of the whole extraordinary space that drawings and photographs can only begin to convey.

 The next step is to attach the new laser scan of the subterranean workings to the digital terrain model of the ground surface generated by the survey in 1995, to create a 3D model of the whole site which can be manipulated and explored digitally. This technical innovation will enable us to study in very precise detail the full extent and size of the mine and to guage for the first time the exact amounts of chalk and flint that were extracted. In addition, the laser scan will be invaluable as a tool for monitoring any structural collapse or erosion in this delicate underground environment. The mine is also home to a colony of bats, and is therefore protected as a Site of Special Scientific Interest.

If you are interested in finding out more about Neolithic flint mining, English Heritage's Archaeological Survey & Investigation Team has produced the definitive book on the subject, entitled The Neolithic Flint Mines of England, published in 1999.

The full report (ref.: AI/9/2000) can be ordered on-line. For more information about the research, contact Pete Topping in English Heritage's Cambridge Office on 01223 582 700 or pete.topping@english-heritage.org.uk

Grime's Graves is cared for by English Heritage and is open to the public all year round, but please note that only one of the three excavated shafts can be entered by the public. In due course, the new laser scan will hopefully allow a means of remote access to Greenwell's Pit, which is sadly too fragile and dangerous to open to large numbers of visitors.