Note: The Lynch Quarry Site, also known as the Lynch Knife River Flint Quarry, and designated by the Smithsonian trinomial 32DU526, is a historic pre-Columbian flint quarry located near Dunn Center, North Dakota. Was a Plains Indians mining site of Knife River flint, a dark, hard rock used to make weapons and tools for more than 10,000 years. Parts of the quarry are so intact that the anvil stones Plains Indians used to break up large flint chunks are still there by the ancient digging pits. The site was on land owned by Allen and Gail Lynch; now the Lynch Knife River Flint Quarry has been designated a National Historic Landmark under the National Park Service.