Kevin Berry discovers how Conisbrough Castle provides pupils with an entertaining and fascinating look at Norman life

"What can you see?" asks Big John. "And I'm looking for a one-word answer!"

"Everything," his audience of windswept teenagers choruses.

On the very top of Conisbrough Castle's magnificent keep we can indeed see everything for miles. This strategically important fortress dominates South Yorkshire's Don valley. It once controlled the border between Mercia and Northumbria.

"Any soldiers moving and we can soon see them," John tells us. "We can see them in the woods, because they will disturb the birds and kick up dust."

John Pilkington is one of the Conisbrough Castle guides. His audience is a group of Year 10 pupils from Outwood Grange College, Wakefield. Today, John is dressed as a Norman steward. He talks as a steward, but more often in the third person. He has everyone's rapt attention. He unfolds life in a Norman castle in a wholly fascinating manner. John compares living through a medieval winter to living under siege, and the comparison is apt.

His description of a castle under attack is also vivid. "Forget this notion of boiling oil," his voice booms out against the wind. "Oil was just too precious to waste on your enemies. You would use red hot sand and boiling hot water. Imagine getting that pouring down on you when you have heavy armour on!"

The lord's fireplace, large but hardly magnificent to a modern eye, would have astonished any peasantry if they were ever allowed to see it.

William de Warren, the first earl of that line, built the first wooden motte and bailey structure at Conisbrough. He is thought to have been the richest resident of these islands in the last millennium, worth £57 billion in today's money.

"I didn't know much about the structure of a castle. Now I do", says Gavin Marshall. "John makes it humorous and so interesting. Rather than get it all from textbooks I feel better with someone speaking to us."

That is a view shared by everyone from Outwood Grange. What they have heard they will remember. These students are curious and John has done much to stir that curiosity. He has many years of experience as a medieval re-enactor and interpreter, as do his guide colleagues.

"I love working here," John says. "Every morning when I walk up the hill I think, well, there she is. And she'll be there long after I've gone."

Conisbrough Castle has outlasted the Industrial Revolution. The view from the keep used to take in a landscape of collieries, terraced houses and railway lines. Now the land is green and pleasant.

Sir Walter Scott set part of his novel Ivanhoe at Conisbrough. The keep is considered to be one of the finest examples of medieval architecture in Europe. That's because a section of outer wall fell away; Henry VIII consequently decommissioned the castle, so it was not used during the Civil War. Over the centuries builders tried to steal some of the stone. There was some damage, but the castle, especially the keep, was too well built.

"I didn't realise there'd be so much history here," says Ben Wildey. "When Big John asked us to try and imagine how people felt, that made a real impact on us. I've learned a lot today."

It is noon and time for the Outwood Grange pupils to get on the coach.

There are murmurs of disappointment because the time really has flown.

*Entry costs £2 plus VAT per child, if the group numbers more than 16, and £2.50 plus VAT per child for a smaller group. Teachers and school staff admitted free