The earliest evidence of human habitation on Lewis is found in peat samples which indicate that about 8,000 years ago much of the native woodland was torched to make way for grassland to allow deer to graze. The earliest archaeological remains date from about 5,000 years ago. At that time, people began to settle in permanent farms rather than following their herds. The small houses of these people have been found throughout the Western Isles; in particular, at Dail Mhor, Carloway. The more striking great monuments of this period are the temples and communal burial cairns at places like Calanais.