Here is the map: https://usgs.maps.arcgis.com/apps/webappviewer/index.html?id...

So basically, wherever there are hills. I mean, I'm sure it is accurate, but looking at my local area I don't see any differentiation between one hill or another, or any additional information I could glean from it that I could not just by looking at a hill and saying, "Yup, that side is steeper."