Here is one of the wonderful mysterious places in Harney County,OR you can visit.
Diamond Craters- Nope you won't find any diamonds here. They no doubt received their name because they are on the road to the town of Diamond. To me they are giant pockmarks on the earth. Diamond Craters is an area of 17,000 acres that has diverse basaltic volcanic features. It's believed these craters were formed the past 25,000 years with some of the eruption has early as 1,000 years ago.
If a villain found one of these craters on the farthest reaches of the area they could torture and leave a person. Only the circling of turkey vultures would give rise to check the area for perhaps dead wildlife.