#Undammed April 20

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What is the longest UNDAMMED river in the United States?

My curiosity stemmed from determining that the 133-mile Lumber River (Scotland-Hoke-Robeson County- Columbus County NC) did not have a dam on it. The river starts at Scotland Hoke County Line until it reaches the Little Pee Dee River near Nichols SC. Red circle on map shows where they come together.

Longest Natural Flowing River

The longest river in the United States without a dam is the Yellowstone River, which flows for 692 miles (1,114 kilometers) through the states of Wyoming, Montana, and North Dakota. The river originates in Yellowstone National Park and flows through the scenic Yellowstone Valley, providing habitat for a diverse range of wildlife and supporting a variety of recreational activities such as fishing, rafting, and camping.

Last summer my wife and I got to witness the Yellowstone River up close. It was beautiful and powerful.

My wife at Calcite Springs Overlook

Both of us at Brinks of the Upper Falls

The Yellowstone River ends it journey a few miles after crossing into North Dakota, where the mouth of the Yellowstone River meets the Missouri River. The two rivers connect near Buford, around 25 miles west of Williston, North Dakota.