Did the Chinese actually come to the western hemisphere before Columbus?

[Jason]

It seems they not only came, but they mapped the whole place. I was browsing YouTube one night and ran into this story. It was very interesting. Have you heard of it? One thing it speaks of is a large wall in California that seems as though only the Chinese built.

 

[Kane]

I have not read anything about this but I believe Chinese were mostly happy in their own world, they did not explore outer words like Europeans. However, in their place they achieved engineering marvels.

 

[Riberet19]

I think that the Chinese are not a race that emigrates a lot, but they are almost always present in almost all countries. I do not have much knowledge of when they began to emigrate to the Western Hemisphere.