According to the latest information available, the US 89 Park County boat ramp in Montana is a concrete boat ramp that is approximately 20 feet wide. It provides access to the Yellowstone River, which is a popular destination for recreational boating, fishing, and other water-based activities.

The boat ramp is suitable for a variety of watercraft, including motorized boats, kayaks, canoes, and rafts. However, it's important to note that certain regulations may apply depending on the size and type of watercraft being used.

Overall, the US 89 Park County boat ramp is a well-maintained and convenient access point for anyone looking to enjoy the natural beauty of the Yellowstone River in Montana.