Morning or afternoon. I avoid the high point of the day from 11:45 to 1:45. Sun is at the highest and most likely to burn.
If you dont get there right around open time or within an hour of open the next best time to get in is around 3pm
If you are new try a few hours at a time with sunscreen and see how they do. Staying away from prime time sub hours is helpful however you can still burn or overheat if you are not used to it.
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