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Ancient River Warren Channel

Ancient River Warren Channel
Ancient River Warren Channel

A channel cut by the Ancient River Warren during the Ice Age, Ancient River Warren Channel contains the Hudson Bay-Gulf of Mexico divide. A lake on each side of the channel provides evidence of the irregularities in Ice Age sedimentation.

Location: Big Stone County, MN ; Traverse County, MN ; Grant County, SD ; Roberts County, SD

Year designated: 1966

Acres: 101,560

Ownership: State, Private

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Please remember, National Natural Landmarks (NNLs) are not national parks. NNL status does not indicate public ownership, and many sites are not open for visitation.

Last Updated: June 28, 2012