Worked from 11,000 BC to AD 1600, and its flint travelled a continent
Knife River flint was the toolmaking material of the northern plains, prized because it works cleanly into projectile points, and this quarry near Dunn Center was one of the great sources of it. People dug here from around 11,000 BC to AD 1600, thirteen thousand years of continuous working, and flint out of this ground turns up at archaeological sites clear across North America. It became a National Historic Landmark in 2011. Stand here and you are at the supply end of a trade network that ran for most of human history on this continent.
Other places on the map within a couple of hours of here.
