STEPHEN LEWIS turns archaeologist to explore York's newest visitor attraction.

IT'S an exciting moment. We are down on our hands and knees in the Fishergate mud, carefully removing the topsoil with trowels. As we scrape away the fine earth, a shape begins to emerge.

Sarah Maltby hands me a soft brush and I use it to clear away the last traces of dirt. It's clearly a bone - a leg bone, it looks like, and from the size and shape, human.

Excitedly, we continue to dig, following the contours of the bone with our trowels and brushes until an almost complete skeleton is exposed - arms, legs, rib cage, even a jawbone.

We are digging on the site of a medieval Gilbertine priory built 900 years earlier. We have already uncovered the stone outline of a centuries-old church wall. Judging by the chalice we found next to this skeleton, we may just have unearthed one of the priory's long-dead monks.

Sarah stands up, and brushes the clinging rubber granules which make up the "soil" we've been digging in from her trousers.

The original of this skeleton, uncovered during a genuine archaeological dig near the site of the Novotel in Fishergate in 1985-86, was indeed that of a medieval priest, she explains.

But even to this day, there is some mystery about exactly who he was.

"We do think from the evidence that this man was a priest," says Sarah, the York Archaeological Trust's head of visitor attractions.

"But what has us puzzled is that a priest would normally have been buried in the church. This man was found outside. So it is a bit of a mystery. Was he a priest from another monastery, who came here and then died and for some reason wasn't allowed to be buried inside? We don't know."

We are standing inside St Saviours Church, in what was formerly the York Archaeological Resource Centre, or ARC.

In a £1 million transformation, the ARC has been turned into Dig, York Archaeological Trust's latest hands-on, interactive museum - a new Jorvik, if you like, but with the emphasis on the whole of York's archaeological past instead of only the Viking era.

Where Jorvik sets out to recreate the Viking settlement of 1,200 years ago, Dig - which opens next week - aims to give visitors the chance to become archaeologists themselves, working on recreations of four York digs covering the city's Roman, Viking, medieval and Victorian past.

ARC has been very successful, says Sarah, attracting something like 30,000 visitors a year with its hands-on approach to archaeology.

"But it had been running for 12 years, and it had just got a little tired. So we thought, what could we do about it? We decided we wanted to keep the hands-on element, but make it a bigger experience than that. And we wanted more about the archaeological process - to create somewhere where kids can have a go at digging."

What they have come up with, Sarah believes, is something unique. Accurate reproductions of the four dig sites, where kids and other visitors can dig through the specially-created rubber "soil" with trowels and brushes, uncovering replicas of the real objects unearthed in genuine digs a few years previously.

The four sites that have been reproduced are:

u The Blake Street dig in 1975, which unearthed part of York's Roman fortress. Youngsters can uncover the barrack rooms and find the remains of military activity - including ancient ammunition, bits of Roman armour and painted plaster from the decorated walls

u The world-famous Coppergate dig of 1976-1981, which revealed as never before what life was like in the Viking age. Visitors can dig down to the remains of a Viking blacksmith's.

u The Fishergate dig of 1985-86, which uncovered the remains of the medieval Gilbertine priory. Finds here include the skeleton of the medieval priest, parts of the church wall, and various grave goods such as the chalice which give clues to the body's identity.

u Hungate - a dig which in real life hasn't even taken place yet, so that visitors are one step ahead of the archaeologists. The dig created here is based on written records and old photos of Victorian Dundas Street, and includes the small backyard, privy and kitchen of a slum house. Budding archaeologists can uncover bits and pieces left over from Victorian domestic life, including children's toys, clay pipes, old coins and bits of crockery.

As you would expect from the team that brought us Jorvik, the attention to detail at Dig is extraordinary.

Visitors enter through a recreation of an archaeological site hut, the scruffy wooden structure put up on a dig site to act as a field HQ. It's accurate down to the last detail, including the hard hats and fluorescent jackets hanging on the walls and the untidy piles of muddy implements such as trowels, forks, brushes and sieves cluttering up one corner.

Here visitors are briefed about the basics of archaeological techniques and procedures, before being led out to the digs themselves.

These are arranged one after another on a sloping "street" that leads up from the Roman dig at the bottom, through the Viking and medieval excavations to the Victorian dig at the top.

Just how much fun this all should be is proved by a party of children on a school trip from Halesowen, in the West Midlands, who are allowed in while I'm there to try it out. They fall on the digs with excited shrieks.

"We've found some old bones and stuff!" says nine-year-old Laura Wolton, who is in the Fishergate dig, turning excitedly to her teacher, Nigel Matthew.

She turns back and continues excavating. "It seems to be a leg bone," says Laura. "Oh! And we've found something else. It's a bit of jaw!"

Further along, on the recreated site of the old Hungate slum, and with chattering children all around, Sarah Maltby hands me a trowel and urges me to dig in the corner.

Gradually, I unearth a strange, square object that seems to be a piece of slate. That's exactly what it is, Sarah says, a child's writing slate. Nearby, right in the corner, I uncover a round, metal object.

It's the base of an outdoor toilet or privy, Sarah says - they didn't have the luxury of indoor loos in Hungate in Victorian times.

"Someone was obviously doing their homework on the toilet!" The children giggle.

For archaeologists, the actual dig is only the beginning of the process of understanding and interpreting our past.

The objects unearthed have then to be studied, analysed, pieced together like a jigsaw and interpreted in the light of historical records and other evidence.

Dig doesn't ignore this. After spending 25 minutes or so digging, visitors pass through a series of other zones.

The "in the field" zone is a recreation of a field tent of the sort set up on established digs to protect important finds. In here, the completely exposed skeleton of the medieval Fishergate monk lies on the ground.

Visitors get the chance to make detailed sketches of the skeleton, using gridded archaeological paper, and piece together the various bits of evidence they dug up earlier.

Next is the Lab Works zone, a recreation of an archaeological laboratory. The centrepiece is a replica soil core from the original Coppergate Viking dig. Embedded in this are bits of archaeological evidence, everything from the seeds used to make Viking bread to moss used as toilet paper and even a - real! - bit of Viking poo.

Here there is also a section looking at how Roman artefacts are preserved and, providing the biggest yuk factor of all, a display on the various bugs found in a Victorian Hungate slum.

Microscopes allow visitors to see the cockroaches, bed-bugs, head lice, fleas and so forth in glorious detail. And a wall-mounted interactive display shows where they would have been found in the house.

Press the button marked "fleas" and a series of bulbs light up on a giant mural of the inside of the slum house, showing exactly where the fleas would have lived. Mainly, of course, on the bodies of house's inhabitants.

Sarah Maltby presses a button marked "tapeworm", and a tapeworm is outlined in tiny bulbs in the stomach of a little girl. "That's my favourite," she says.

The Lab Works Zone and the Study Zone - which recreates an historian's study - are designed to help budding archaeologists piece together the archaeological puzzles they uncovered earlier, and to interpret them in the light of scientific evidence and written and other records of the time.

Finally, visitors emerge into a central hall where they have the chance to look at real objects discovered on the digs they have been following, all presented in neat glass cases. There is also the chance to ask archaeologists' questions.

It all adds up to a fascinating exploration of York's past that gives a real insight into how archaeologists work - and how they piece together the past from the bits of remaining evidence they uncover in the present.

A worthy partner attraction to Jorvik if ever there was one.

Updated: 10:19 Thursday, March 16, 2006