I did the tour when I was a kid. I wasn't too impressed with the hills, cuz I don't think we were allowed to climb on them. The highlight was some kind of outdoor showcase that contained the bleached out bones of some poor soul.
From ground level, the mounds look pretty much like grassy berms.
Yeah, but it's nearby and probably doesn't cost anything. My kind of tourist attraction! I just showed the map to my husband, and he's never heard of it either. Probably we'd know about it if we'd raised kids here, but we moved here after all the kids were out of college.