What time do they close? Are they open every day?
When we were there, they closed at 5.00 & are open daily. You'll find that your Tuk Tuk driver or taxi driver will know what the hours are for all of them. They will also know what time to go to avoid the bus loads of people! Hope you have a ball :-)
As far as I know, they are opened everyday. You buy the ticket from the same counter as Angkor Wat - 20dollars, and you get access to temples in the area (you can have a map to see how many are included). The ticket can be bought starting 5:30 (everybody wants to be at the sunrise at Angkor). The latest entry time is around 17:00, 17:30. I did not stay pass 18:00 so I do not know the latest hour when you can access.
Preah Khan is part of the Angkor Wat complex which means that you gain entry via the complex entry so you need your complex pass. The last entry is around 5pm with people generally expelled around 6pm or maybe a bit later.
If you don't have a ticket then the ticket office opens at 5:30am, if you have a ticket then we got in around 4:30am for the sunrise.
They are open every day but there maybe religious days they are closed but as far as I know it is every day. We were there Christmas Day for example, as it is a non Christian country it was open as normal.
I think they are open everyday! I didn't see the schedule for this one, but I think it's around the same time as angkor Wat, 18h!
It may happen they'll be closed some specific holy days or to do maintenance!
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