Question

1. The Yosemite is famous for its natural wonders.
2. Yosemite Valley is famous for its natural wonders.
3. Yosemite National Park is famous for its natural wonders.
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Do we put 'The' before Yosemite? Does #1 mean #2 or #3?

Answer 1

I'd say all are ok.
"The Yosemite" would indicate the general area where the Park is located.

The valley probably includes more area than the park alone, but would indeed be called by its name, without "the."

Answer 2

“The” is not used when referring to either Yosemite Valley or Yosemite National Park.

If you look at the whole park on a map, you see that Yosemite Valley is one part of the whole. Another part is called Tuolumne Meadows. And there are more named sections.

https://images.app.goo.gl/nW6bX97vxnTtGrme9