Picture a castle and you may see crowds of soldiers on the walls. In peacetime the truth was different. A small castle might have a garrison of only a dozen soldiers or fewer, just enough to open the gate, work the portcullis (a heavy grille across the entrance) and drawbridge and patrol the walls against stray robbers. Castle owners did not live in each castle all the time. The kings of England owned dozens of castles and could never have visited them all.

When an owner did arrive, the castle filled up. Countess Joan de Valence arrived at Goodrich Castle in 1296 with a long procession of carts and waggons, over 50 horses and 194 followers. A castle also had servants.

Their life was not easy. Lowlier castle servants slept anywhere they could find and in summer worked from 5.30am until about 7pm, with few days off and little pay. But they were given uniforms in their lord's colours and regular meals all year round. Castles were places where people lived and worked, not only forts.

Knights were part of the story too. A knight's armour and heavy horse were expensive to buy and keep, so the king, in return for knight service, gave land as an incentive. Armour kept changing. As it grew into full plate by the 15th century, knights seemed unstoppable, until powerful firearms capable of puncturing plate armour arrived.

Even the stones carried marks. Medieval masons put a unique mark on the stones they cut so that they would be paid for them. You can sometimes spot these marks in the stones of old buildings. One well was very deep. The Fore Well at Edinburgh Castle is 34 metres deep, which is about as deep as two very tall trees.

Some castles were tested again and again. Edinburgh Castle was besieged around 50 times. Murder holes were holes in the roof of a gatehouse passage through which missiles could be dropped on attackers. At Beaumaris Castle, at high tide, ships could sail into the dock and unload supplies directly into the outer ward, a part of the castle, through a door in the wall.

Words to know

• garrison: castle soldiers
• masons: stone workers
• procession: long line
• besieged: surrounded and attacked