When I lived in Arizonia I would take my horses and ride off into the dessert on weekends, and any time I had a few days off. I was just exploring, and having a good time being out by myself.
One day I was in some mountains west of Pheonix, exploring when I decided to check out a canyon I had explored in before. I had found what looked like steps cut into the rock going up on a previous trip. I rode back up there and as it was getting late I made camp against the southern wall where it was cooler. In the morning I went walking up near the face of the southern wall and turned around looking at the opposite side of the canyon and saw a massive area back under the rocks coming into view. The morning sun was shining back into the area and I could just see what looked like a laid up stone wall.
Later in the day I crossed over to the area where I had seen what looked like steps and tried to climb them. They led up and over a big cliff face. Once on top it was easy walking to another sheer face, where better cut steps led up the wall. I climbed these and eventually came to easier climbing. Suddenly I came to the top and there was walls and roofed buildings. Stones had been laid up making the walls. At one time mud had been covering the walls, but it had fallen off in most areas. I walked around finding broken pottery, and pieces of wood lying in corners. There were fire pits where the stones were still blackened from ancient fires. I did not disturb anything, I realized what a great discovery I had made and wanted to make sure treasure hunters and vandals did not find the area.
I notified the University Of Arizona, and took them out there the following weekend. They were ecstatic about the find, and the fact it was totally undisturbed. Although one guy felt I had taken some things and could not get over the idea that I had not touched anything. The University said I would be credited with the find, but asked that I never tell anyone the exact location since they had no way of securing the area. They wanted to keep it secret till they had examined it well. It's now been over thirty years and they have not finished with their digging and cataloging the area.