Lynda Hillyer: This is one third of a very important 15th Century tapestry which measures 7.5 metres by 4 metres. It was woven in Tournai in Northern France in the 15th century. The whole set was eleven tapestries, so it was an enormous amount of wall covering.

Charles VIII of France hung the whole eleven tapestries at a reception after his marriage to Anne of Brittany in 1491. It's a fantastic idea to think of eleven of these tapestries all being hung covering the castle walls. This is part of the ninth in the series and the whole story in the tapestries is about the Trojan Wars.

How is the tapestry made?

All textiles consist of a warp and a weft. The warp, which forms the basic structure of the tapestry, runs in this direction - horizontally. The weft, which forms the colour and the pattern, comes up and over each warp. It's called a weft faced plain weave. If you look closely at this damaged area, you can see that the coloured weft goes over and under the plain warp and covers it completely.

How is the tapestry conserved and cleaned?

Because tapestries could be taken down from the walls and moved from house to house, or castle to castle probably, they were handled a lot and they often didn't fit into another castle or house, so often you might find a doorway's been cut out.

In the case of this tapestry - which is very, very wide, it's 7.5 metres wide - it was probably too big to fit into another house so it was cut into three separate tapestries.

Tapestries can suffer from moth damage, from mechanical damage, they can be torn, they've had a long life. This is 500 years old, we don't know what its history has been.

For example, here, a large piece has been torn out and been repaired with a piece of linen. You can see a patch on the back.

In very large areas they have painted the linen to try to make up the loss of the colours and the pattern. The colours in this tapestry are still remarkably good, but they are a little bit faded. If you look at the back you can see that they are more vivid.

In the 15th Century all of the dyes would have been natural dyes. The red for example could have been madder, which comes from a plant, or it may have been a dye called kermes which is made from crushed insects.

It's been thoroughly vacuumed because it was quite dusty. Tina has been taking out a lot of the old repairs and the old patches. It's then going to go to a special installation in Belgium for wet cleaning.

The installation consists of a very large room, the floor of which is perforated. The tapestry is laid on the perforated floor and water vapour mixed in with a special detergent is drawn through the tapestry and the perforated floor by means of suction. So it is a giant suction table.

It's a very safe way of cleaning a large tapestry because there is no handling involved, we don't have to move it when it's wet which is when it's much more vulnerable. You see here the whole process.

After the cleaning has been carried out the tapestry is blotted dry with this cotton sheeting and then warm air is pulled through the tapestry again by suction. So that the whole process is complete within about eight hours. And you can see how efficient it is.

These are samples of the rinse water from this tapestry which has just been washed. You can see it started out very, very dirty until it becomes much clearer and cleaner.

After it's been cleaned it's going to be completely supported. The tapestry will come back from Belgium to the textile conservation studio in the V& A. It will be put on to a tapestry repair frame. Also on the frame will be a roller of this linen scrim which is an open fine-weave linen. And the entire tapestry will be stitched on to a complete support of this linen scrim to hang completely safely.

We estimate it will take approximately 3500 hours. So that's three working years for one conservator.