If you've been fully vaccinated you can still go, even if you live outside of California. If you aren't, then I wouldn't risk it. I went to Six Flags yesterday and they ask for ID. I showed my driver's license, which has my permanent address on it, but if you show them ID that doesn't have a California address on it, they'll probably want to verify it through other means.
They do have a way of checking... and will, based on identification, and documentation. Keep in Mind, Magic Mountain was one of LA County's Main VACCINATION Sites, up until a couple of weeks ago, when they decided to open back up to the Public again. So come correct, bcz they are turning Non-elgible folks away.
Yes you're fine. You can purchase tickets
Yes, they have no actual way of checking
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