The circle in the picture is approximately 50 cms. in diameter.  The painting is on the ceiling of a small sandstone cave and is in danger of being sand-blasted away by the wind.  It is in my opinion that this pictograph panel is one of the most "beautiful" within the United States and should be saved from destruction by the local weather environment, and possible thief by "pothunters and art thieves." 

Chumash
Kern County, California
 

Notice how the wind-damage has removed a large area of the panel surrounding the remaining panel.

You will find that  later paintings have been superimposed over earlier work.

Chumash
Kern County, California