Visitors center is nice. Main path goes to the Windmill pasture and is where the Buffalo roam, literally. It does go uphill, but the path is wide with packed gravel. I would guess roughly a half mile to the entrance of the pasture. There is an old school house and a couple of other older buildings, closer to the visitor center, less than a quarter mile, that does have a road going to them. It's all free so worst is your out travel time to get there.
The buildings are all near the road and parking.
You can also see the historic school house. It has its own parking lot.
They have a free bus tour.
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