The area below the head, bottom of the bend and throat of snake......I just emailed this back to him, but forgot to mention the pasted part of snake carving, needed to be flipped horizontally, oriented correctly on the hole or cave photo. It looks like a cave entrance or deep hole/pocket mine, can't tell for sure from the pic.. It appears the snake rock, to be a trail marker. A freehand selection from the snake is pasted above on the hole photo (flipped horizontally).