Turns out there are two Cliff cemeteries -- a Catholic one and a Protestant one. I've been to the Protestant one many times, which is just off Cliff Drive, in the shadow of the cliffs, near the rest of the mine ruins.
However, on US-41 about a mile from the north intersection with Cliff Drive, there is a small sign on the side of the road which say "Cliff Cemetery". For years, I'd drive past it and think, "Boy, that sign sure is a long way away from the cemetery, it's not even on this road!" Then one day I actually stopped to look, and sure enough, just down from the sign there is a tiny little path going into the woods. It passes a tiny stream, past some huge old trees, and through a patch of thimbleberries. All of a sudden, the ground becomes covered entirely by some very low-growing dark green leafy shrub, through which very old headstones poke up. There's also a very old poor rock foundation, maybe from a small chapel, and a small stand of pines.
Edit (2/18/2009): Recently I had an email conversation with Mary Drew over at pasty.com. She had looked through my blog, found this post, and passed along this story about the grave in my photo:
I have an Adult Foster Care Home where I care for 6 residents, some elderly, others not so elderly, but just needing assistance to get through each day. One of our elderly residents up until she passed away at 96, was a sweet little lady named Irene. [The grave in this photo] is her Grandfather's grave and her Father and she, planted the flowering ground cover you see in the photo there around his grave, then it spread and started covering everywhere. I think it's called phlox. Up until the last couple years Irene lived with us, her nephew (who is 78) would take her up there to the Cliff Cemetery each summer and they would take the short hike in to visit her Grandfather's grave. My husband and I have been there several times since she passed away, just to pay our respects to Joseph and the others buried there.
What a wonderful story! (And now we know where that nifty ground cover came from.) I wish that I'd had a chance to talk to Irene about her memories. Mary also mentioned that, a few years back, some group of people was doing interviews with people who remembered the Italian hall disaster, for the purpose of making a documentary. Neither of us knows anything about that documentary though -- anyone out there have an idea?