Later, Yangshao culture was superseded by the Longshan culture, which was also centered on the Yellow River from about 3000 to 1900 BC, its most prominent site being Taosi. The population expanded dramatically during the 3rd millennium BC, with many settlements having rammed earth walls. It decreased in most areas around 2000 BC until the central area evolved into the Bronze Age Erlitou culture. The earliest bronze artifacts have been found in the Majiayao culture site (3100 to 2700 BC).
