This is a bend in Huang He in Qinghai, the closest to the source of the Yellow River that I have even been to. And it was just beautiful. The river turned 180 degrees in a sharp bend.
The sun was setting when we got there, the moon has already risen, and the last sunrays painted everything yellowish.
I have already seen Huang He near Hancheng （韓城）, between Shaanxi （陝西）and Shanxi （山西）, in the middle ranges of Huang He. There the river was wide and muddy, really yellowish.
I have also seen Huang He at Lanzhou （蘭州）, in Gansu （甘肅）. There it was angrily, boilingly reddish-yellow in summer; but clear and greenish in winter.
Now I have seen it even closer to the source in Qinghai（青海）. It was clear and greenish-blue in winter, much like it was in Lanzhou. It seems the closer it was to its source, the clearer and greener it gets.