Where is the twon

The inhabitants of the site had tried to hold back the sand as best they could, but over time it rendered agricultural land useless covering fields, houses and eventually even Kenfig Castle itself. For us it was a hindrance to our exploration of this lost town, Kenfig in South Wales.

Sand. It's great if you're on holiday at the seaside. It's useful if you want to mix concrete. Not so great when there are metres of it covering the archaeology you want to get to in a vast series of dunes. Now a pretty nature reserve, the dune system is home to rare plants and animals. Having taken all the necessary precautions not to disturb this natural idyll, Phil and the rest of the archaeologists had to figure out how to get through the sand safely and, more importantly, where to dig.

It wasn't just the volume of sand at the site that would be a challenge. Sand is a dangerous substance to dig through. The sides of trenches are not solid and could collapse at any time. In field archaeology a safe method of excavation in sand or other insecure material has been developed. A trench can only be 1.2m deep before it must be 'stepped'. This means that the trench is widened out, ensuring the safety of excavators, before digging can continue. This is time consuming work and results in a very small surface area of archaeology being eventually exposed.

Despite the sandy problems the dig was very successful. Excavation revealed very well preserved archaeological deposits, showing high status administrative buildings, well-built roads and evidence of industry and agriculture. Once the filming and three days excavation finished however, much more work remained to be done.

When the cameras and presenters leave our excavation team, led by Wessex Archaeology, remains behind to complete a record of the archaeology we have discovered. This means cleaning up trenches, drawing sections and plans, taking photographs and bagging and cataloguing all finds. Once the team is happy this work is complete, the trenches need to be safely backfilled and the site returned to a condition that the landowner is happy with. Our team took several days to complete this work at Kenfig since the archaeology was complex and required detailed recording.

The final stage involves backfilling all the trenches. At Kenfig the sheer volume of sand moved during the dig meant that it took two days to return the nature reserve to the condition in which we had found it - entirely covered by the sand.