Celtic Iron Age homes were generally timber framed round houses with conical thatch roofs. Doorways were low and protected by a porch to keep out wind and rain Spaces between the timber posts making up the walls were filled with woven branches of willow and plastered with straw, clay, mud and animal dung on the outside to form a waterproof shield (wattle and daub) and then whitewashed with lime on the inside if you wanted to be fancy. Roof timbers were covered with a thatch made from reed or straw. Grain was kept in underground pits or storerooms and domestic animals often shared the same space as their owners. While most houses were round, the great halls at Eamhain Macha or Cruachain were rectangular.
Noble women often had exclusive use of a Grianán (a sunny bower) but furniture was limited to rough boards or trestle tables and stools or benches. Beds usually comprised of mattresses made of straw covered with animal skins and nearly all residences were surrounded by strong defensive walls.
Lake villages were built on artificial islands – crannogs – linked to the land by narrow wooden bridges.
Settlements were called Ráth or Lios and situated at or near the mouths of rivers. Something a bit more substantial or a noble residence was called a Dún. These, usually, hilltop forts were made by heaping up huge banks of earth around the summit of a hill and then topping these ramparts with wooden walls made by rows of sharp stakes driven into the steep earth banks.
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