UPDATE. Anyone can reserve free tickets online for weekends.
They have scheduled tours that can be found on line.
Amazon is going to open the Spheres to the public a fee days a month, so call them or look online at their web page. You can also go with an employee as their guest anytime.
The bottom part with the botanical expo is open to the public. The rest requires you to be the guest of an amazom employee.
AFAIK it's generally not open to the public but any employee of Amazon's can take you.
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