it's possible....but little far ....neither a small cave as the same picture but it is hidden in rock..nor a target in rock hole like a small well..
but no doubt the direction is as i told you.
if you could give me a farther picture to see what is surrounded the sign it will be more clear and also tell me how long is this snake ? use a thread on the snake then measure it..i think it will be between 17 - 20 cm.