As the coach drives towards Flag Fen near Peterborough, some of the younger pupils have a look of bemused tolerance that seems to say, “I’m only here because the grown-ups brought me”. And who can blame them as they pass a flat, empty landscape of green fields interrupted only by drainage dykes?

At first sight, the area is not the most exciting place for a school visit, but by the end of an introductory session which has seen pupils from Fulbridge Infant and Junior Schools dressed up in primitive costumes, there is an atmosphere of excitement. A third of the party become engaged in a treasure hunt around the museum, fascinated by artefacts and by a 3,000 year-old wheel. Another group sit in a replica Bronze Age roundhouse, hearing the domestic details of prehistoric life, while the remainder are engaged in an archaeological dig.

Flag Fen is an amazing place. A few kilometres east of Peterborough, its treasures were discovered in 1982 and it was rapidly assessed as one of the most important archaeological sites in Europe. Here, a 3,000-year-old line of posts still runs for nearly a mile from this eastern edge of Peterborough (once the shoreline of the North Sea) across a low-lying fen to what was an offshore island. In the wettest part of the fen, the builders of this “post alignment” made a platform, nearly three acres in size.

Archaeologists use the term “post alignment” because they are unsure of its precise purpose. It was almost certainly a kind of bridge or walkway and, from the many relics that have been discovered, was probably used for religious ceremonies up until Roman times - and possibly later.

Because Fenland has been heavily drained in the last few centuries, much historical evidence has decayed on coming into contact with the air. Flag Fen’s timber work has been preserved by being submerged in the wetlands and a large Preservation Hall now houses a semi-submerged section of the post alignment.

Obviously, this part of the site is not suited to hands-on activity and the way Flag Fen embraces Iron and Bronze Ages and Roman history can make its story a little confusing. Mike Lewis, the site’s education officer, is aware of this but is equally determined that any visit should, primarily, be fun. “We tell the story a little bit at a time and without any boring lectures. For example, we explain the principles of archaeology by getting them to discover specially hidden objects and fragments in the sand. They describe what they’ve dug up, then we get them to tell us what they can deduce from the objects.”

This was a special activity chosen by Fulbridge infants and juniors.

Although a visit to Flag Fen is ideally suited to pupils aged eight and over, activities can be adapted to suit all ages. The school could have chosen to make clay finger-pots, gone on a prehistoric nature walk or listened to a specially-booked storyteller. For older pupils, Flag Fen will tailor programmes, such as one which explores the purpose of archaeology.

Toby Lewis, the site’s general manager, says that although the Bronze Age isn’t part of the history curriculum, Flag Fen is a valuable resource for teaching science, geography and design and technology. It also fits naturally into any project on invaders and settlers.

By the time the children of Fulbridge leave they have a clear idea of what “prehistory” means and are aware that their ancestors, who once lived on Flag Fen, were part of a sophisticated society.

Entrance fee pound;3.50 each for school visits, with worksheets included.Open every day 10am - 5pm including weekends except Christmas, last admission 4pm