The short of it all is that the gates stay open
Between March 1 and September 1 (despite the gates being open all the time) the official hours are 7:30am to the earlier of either sunset or 7:00pm. From Sept 1 to Mar 1 the closing time is 5:00pm. Having said that, it is rarely ever enforced.
The gates stay open and they never the gates. It doesn't have any post times.
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