Any chair you can lug that reasonably fills a space for one person and won't block the view of those behind you. Blankets are also okay, but they tend to spread outside the lines painted as rows, and being on the ground puts you at a disadvantage. Standing may or may not be permitted. I do know that some kind of a ruckus caused by standing people blocking sitting resulted in ejection of the participants. Not sure who was in the right, but civility would have been better.
low or high dont bring the umbrella chair so you dont block any ones view
The lightweight camp chairs are what we typically use.
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