The Museum of the Fur Trade is Chadron's best reason to stop. It stands on the site of the Bordeaux Trading Post and uses thousands of artifacts to explain the North American fur trade, from trade goods and firearms to clothing, tools, and the relationships between traders and Native nations.
The museum is small enough to visit without fatigue but serious enough to change how you read the High Plains. If you only have time for one sight in Chadron, make it this one.