Time Team had been invited by the National Trust for Wales and Cadw, the Welsh body responsible for heritage, to investigate an intriguing site on the Pembrokeshire coast. Well, just off the Pembrokshire coast to be precise. Gatehom is a rocky, almost inaccessible promontory which, in the past, had been connected to the mainland by a land bridge. This link had long since fallen into the sea, leaving an island surrounded by razor sharp rocks and accessible only at low tide. The island contained a number of intriguing earthworks that had split archaeological opinion. Were they prehistoric? Roman? Viking? Nobody had any idea. For some of our team it meant strapping on the climbing harnesses and helmets, crossing to the island on a zip wire and preparing for some pretty extreme archaeology.

In order to access the island we called on the assistance of Trevor Mussiah and his expert climbing team. It seemed to take forever to get team members and equipment over to the desolate island. It all seemed to be worth it as the island was covered in structures, trackways and other mysterious features. If this wasn't enough we had set ourselves the task of investigating a feature on the coast itself - a prehistoric promontory fort. Could the two sites be linked? With Francis working to uncover the mysteries of the island and Phil working at the fort we had plenty to be getting on with. Our task was to obtain a dating sequence for the two sites and establish whether they were linked.

Previous excavation on the island in the 1920s and 1930s had made a number of exciting finds, from a number of different period... So what were we dealing with? Back at the promontory fort John had completed his geophysical survey. The results were unclear and confusing. Very little evidence of settlement, which we had been expecting. After some debate it was agreed to place trenches over geophysical 'anomolies' that could represent pits. Phil was happy that evidence from his fieldwalking proved the site had been occupied for at least 8000 years - back into the Mesolithic. At the end of the day finds from Rakshas trench on the island were... Roman. Our coastal complex was turning out to me more interesting than we could have hoped.

By day two the team were getting into their stride. Our work had become more urgent as we had warnings of rain and the time pressure getting team members to and from the island on the zipwire. Luckily work could crack on in the fort and evidence had begun to appear to suggest occupation inside its enormous defensive banks. However, it was the island that still presented us with a serious challenge. Raksha and her team were working hard and had uncovered evidence for occupation. The buildings seemed to be early Christian but the finds were Roman - were we looking at an early medieval site importing Roman wares? Ian's trench on the island simply compounded the problem - an early Christian building with Prehistoric pottery inside it, and Matt wasn't helping - a prehistoric roundhouse. Every time we thought we had a grip on what was happening on the island the trenches seemed to throw up more questions. Could we resolve the site in the day we had left?

As day three began, with rain into the bargain, it became clear that this part of the Pembrokeshire coast had been occupied since the Mesolithic period. The island had clearly been in use in prehistory, only to be remodelled and reused in the late Roman and early Christian period. The fort had been a substantial construction that had certainly been in use at the same time as the island was occupied. By the Roman period it had fallen out of use.

So had we been successful in our three day quest? To an extent... We had certainly demonstrated the longevity of occupation at both sites and had shown they were linked through buildings and pottery types. The site had clearly been important to trade and had been a busy settlement. Perhaps archaeologists will return to the site one day to build on the work we have done - they just better be prepared to use a zip wire...