Technically you can enter anytime between 8am to 10pm. If you are going for day use, please leave before 10pm. If the office is closed pay by selfpay station. The trails closes 30min after sunset so better to start early.
No
You can but not advised, you can do in any park, but not advised.
Not that I know of but you would not have time to make it to the top and back down before it gets dark
Not really
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