Let's cut to the chase. It's not "Zion's National Park". Nor is it "Zion's". Zion ain't a person, and he doesn't own the park. IT'S JUST ZION.
Z I O N period.
But don't just take my word for it, take a good long gander at the actual park sign:
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See the apostrophe and the "S" after Zion? Yeah, me neither. Now, that said, see if you can identify what's wrong with the following sentence:
"We're going to go on a National Park tour. We'll start at Yellowstone's, then hit the Grand Canyon's, Yosemite's, Bryce's, Capitol Reef's...and end at Zion's."
(choose your own adventure blog, ala those books way back in the day):
If you identified 5 errors please go to the beginning of this entry. If you identified 6, please continue to the follow paragraph.
Congratulations, your comprehension skills are most impressive. The End.