It is Archaeology Day at Rievaulx Abbey tomorrow. STEPHEN LEWIS takes a trip back in time.

SIX hundred years or so ago one of the Cistercian monks of Rievaulx Abbey got up in the middle of the night to take a pee.

He used the old ale flagon kept standing in a corner of the monks' dormitory for just such purposes - urine was a valuable commodity in those days, useful in the tanning process.

He must have stumbled and knocked the flagon over, and it fell into the reredorter, the great stone-lined sewer that ran beneath the abbey. "And there it settled for the next few hundred years," says John Lax, English Heritage's head custodian at Rievaulx.

It lay undisturbed until a couple of years ago, when two tourists from the United States spotted it lying in the open end of the reredorter.

It's just one of those little discoveries which helps archaeologists piece together the lives of people who lived hundreds of years ago. The flagon was made in Germany, John says - an indication of just how far the trading links stretched of what was one of the wealthiest monasteries of medieval England - and would originally have been used to store beer or ale, before being downgraded to use as a portable urinal. Until the clumsy monk knocked it over in the dark, that is.

A detailed replica of the flagon is just one of many objects that will be on display tomorrow, when the abbey holds its second Archaeology Day.

The day aims to give us an insight into how archaeologists can reconstruct the lives of people long dead.

Visitors will be able to handle many of the artefacts found at the abbey in recent years, study aerial photographs and overlay them with ancient maps to see how archaeologists identify sites of possible interest, and examine 500-year-old pollen grains under a microscope which gives a clue to the plant life in the area at the time and hence the diet of the monks.

There will be a last chance to see the abbey's reconstructed medieval iron furnace in action, guided tours of the abbey itself by 'Brother Anthony', and a guided walk to the nearby 'grange' - abbey farm - of Griff, where hundreds of years ago lay monks would have gone about the business of growing the food that supported the monastery.

Visitors will even be able to go where no man has gone before - deep into the hidden underground channels of the abbey's great sewer, a place unseen for 500 years. Not literally - but by watching recently-filmed footage taken when a mobile camera was floated down the sewer.

Squat at the open end of the sewer and you can look along its length to the arched and silted-up hole where the camera disappeared.

The moment may not quite have been on a par with the discovery of Tutankhamun's tomb - but the ancient sewer holds valuable secrets, John says. Bits and pieces of pottery, timber, pollen and seeds, and possibly, preserved in the centuries-old silt, the remains of monks' meals. Taken together, they all help to tell us a good deal about the lives the monks led.

Those lives were hard. Rievaulx may have been one of the wealthiest and most powerful monasteries in England - but life was no picnic. In its heydey under Abbot Aelred in the 12th century, it was home to 140 choir monks and about 500 lay brethren.

All were bound by strict monastic codes of austerity. They were celibate, enjoyed little privacy, and devoted their lives to worship, manual labour and working on beautifully illustrated religious manuscripts in the abbey's unheated, chilly cloister. Talking was forbidden most of the time, there were just two simple vegetarian meals a day, and year-round monks wore the same coarse habit of undyed, heavy wool with a cowl to cover the head. Fine in winter, perhaps - but very hot and heavy in summer, John suspects.

What the monks got in return for leading this life of obedience and devotion was security - and the knowledge that they were bringing themselves closer to heaven.

"Religion was the key benefit," John says. "But then came other fringe benefits: regular meals, safety and security. It was a turbulent world of famine and war. Life in the abbey was hard, but life outside would be worse."

There are signs that towards the end, life in the abbey did become less ascetic. By the time Henry VIII 'suppressed' the monastery in 1538, the Abbott had one of the finest houses in the area and lived the life of a feudal lord. Even the monks were enjoying better conditions: meat had probably crept into their diet, John says, they may have enjoyed a little more privacy - and even the architecture of later sections of the abbey is more ornate.

Some of the lay brothers may have been a little less strict in adhering to their vows of chastity, too. They helped to run the monastery's many granges, which were scattered throughout the north of England as far away as the Dales and South Yorkshire. That meant many of them were some way away from the Abbot's controlling influence. "The lay brothers who worked the granges at that time would sometimes be a bit loose in their living," John admits. "There would be women there where they should not be, and maybe drink, and sometimes fights broke out. Various things that should not have been going on."

Tomorrow should be the perfect chance to find out about them.

Dig this...

Rievaulx Abbey, near Helmsley, is open daily from 10am to 6pm. Archaeology Day events tomorrow take place between 11am and 4pm. The cost of entry will be slightly higher than usual: £5 for adults, £4 concessions, £2.50 children, with children under five getting in free.

Updated: 14:52 Friday, June 27, 2003