This will be the southwest of Qinghai Lake in Qinghai Lake. If it is Optimus Prime, you can see thousands of stones, but if it is cloudy, you can't see it. His legend is that Sun Wukong and Ella Erlang god fighting when he sent it, took three stone pots to prepare for cooking, just grabbed a handful of salt, the teacher kicked the pot to the lake and finally entered the water is salty, just kept.