They were built using nearby materials from the forests.

The wall of a roundhouse would be made from wattle (woven wood) and daub (straw and mud) which dries hard to keep the inside well insulated and warm.

Inside a roundhouse you might have found:

• a loom for weaving cloth;
• a hearth or fire in the middle that would be lit all the time for: heat, light, cooking and smoking food;
• a dome-shaped oven for baking bread;
• a quern stone for grinding corn;
• beds with hay mattresses and woolen blankets;
• baskets for storing food or belongings.

The Celts also built over 4000 hillforts on the top of large hills. These had high embankments (mounds of soil) and deep ditches (holes) around a group of roundhouses to look impressive and to defend them from raiders.