The Bronze Age, which came to Ireland around 2000 BC, saw the production of elaborate gold and bronze ornaments, weapons and tools. There was a movement away from the construction of communal megalithic tombs to the burial of the dead in small stone cists or simple pits, which could be situated in cemeteries or in circular earth or stone built burial mounds known respectively as barrows and cairns. As the period progressed, inhumation burial gave way to cremation and by the Middle Bronze Age, remains were often placed beneath large burial urns.