Ancient River Warren Channel

The plaque names a channel and says nothing of the river that cut it. Glacial Lake Agassiz first spilled over the Big Stone Moraine here about 13,500 years ago, and River Warren, its outlet, ran through this gap until roughly 10,650 years ago, cutting a gorge about a mile wide and 130 feet deep. The river is named for Gouverneur K. Warren, the army engineer who explained the valley in 1868 while surveying railroad routes. The landmark designation dates from 1966, a year before the date cast here.

What the plaque says

Ancient River Warren Channel Has been designated a Registered Natural Landmark Under the provisions of the Historic Sites Act of August 21, 1935 this site possesses exceptional value in illustrating the natural history of the United States U. S. Department of the Interior National Park Service 1967

Where it stands

Worth the stop nearby

• Joseph N. Nicollet Tower and Interpretive Center — 12 mi
  A tower on the edge of the Coteau des Prairies honoring the French mapmaker who drew this country in 1838 and 1839 and kept the Dakota names on the map.
• Sica Hollow State Park — 20 mi
  Wooded ravines on the edge of the Coteau, on the Lake Traverse Reservation, where the springs run iron-red and the Dakota tell of a good land gone bad.

More markers nearby

• Travare — steps away
• Stones from Log Flour Mill — 9.5 mi
• Map of Northeast South Dakota — 12 mi
• John Otherday — 14 mi