In the Chinese classic "Zhuangzi", there is a legend:
Once upon a time, a gigantic fish named Kun lived in the northern sea. No one knew its true size. This fish could transform into an enormous bird called Peng (roc), measuring thousands of kilometers in length. When Peng spread its wings, they blotted out the sky like vast clouds. In one mighty flight, it could soar from the northern sea to the southern sea on the other side of the world, reaching heights of ninety thousand li (approximately forty-five thousand kilometers).
This idiom, "A Roc's Flight of Ten Thousand Li", is now used to wish someone a long, successful career and a brilliantly promising future.