4000–2700 BC – The Funnelbeaker culture, Scandinavia, originated in southern parts of Europe and slowly advanced up through today's Uppland. 3300–2900 BC – Construction of the Newgrange solar observatory/passage tomb in Ireland. c. 3100–2600 BC – Neolithic settlement at Skara Brae in the Orkney Islands, Scotland, is inhabited. Construction in England of the Sweet Track, the world's first known engineered roadway. Garth tsunami in the Northern Isles. c. 3100 BC – The earliest phase of the Stonehenge monument (a circular earth bank and ditch). The Céide Fields are developed, the first signs of the eventual complete deforestation of Ireland. c. 3300 BC – Ötzi the Iceman dies near the present-day border between Austria and Italy, only to be discovered in 1991 buried in a glacier of the Ötztal Alps. His cause of death is believed to be homicide. Central Asia 3500–2500 BC – Afanasevo: Siberia, Mongolia, Xinjiang, Kazakhstan—late copper and early Bronze Age. c. 4000 BC – Horses are domesticated in the western Eurasian Steppes in what is now northern Kazakhstan (see the Botai culture). East Asia Neolithic Chinese settlements. They produced silk and pottery (chiefly the Yangshao and the Longshan cultures), wore hemp clothing, and domesticated pigs and dogs. 4000–2500 BC – Vietnamese Bronze Age culture. The Đồng Đậu Culture, produced many wealthy bronze objects. South Asia Mehrgarh III–VI 3500 BC Metalcasting began in the Mohenjodaro area. 3300 BC – Bronze Age starts in Indus Valley (Harappa). Drainage and Sewage collection and disposal Ochre Coloured Pottery culture Americas c. 3600 BC – In Colombia, first rupestrian art Chiribiquete (Caquetá). c. 3000 BC – First pottery in Colombia at Puerto Hormiga (Magdalena), considered one of the first attempts of pottery of the New World. First settlement at Puerto Badel (Bolívar). c. 3600 BC – Evidence of maize domestication appear in the Valley of Tehuacán. Norte Chico civilization in Northern Peru starts. Australia c. 3000 BC – The Sydney rock engravings in present-day (Sydney, Australia). Sub-Saharan Africa Sub-Saharan Africa remains in the Paleolithic period, except for the earliest neolithization of the Sahel following the desiccation of the Sahara in c. 3500 BC. As the grasslands of the Sahara began drying after 3900 BC, herders spread into the Nile Valley and into eastern Africa (Eburan 5, Elmenteitan). The desiccation of the Sahara and the associated neolithisation of West Africa is also cited as a possible cause for the dispersal of the Niger-Congo