The castle was built on top of a large artificial or natural mound (the motte), surrounded by a deep ditch. Around this was an area of land called the bailey. Inside the bailey were various buildings for the people who lived and worked in the castle, including stables, storehouses, bakeries, kitchens, cottages, and quarters for soldiers. The bailey was surrounded by a wooden palisade and an outer ditch, or fosse. Sometimes the fosse was filled with water diverted from a nearby stream. There are no good examples of these early motte and bailey castles remaining. Most were rebuilt in the early and mid 12th century as stone donjons, or keeps.