Jaguar Inn Exchanges US dollars cash and traveler's checks.
Everyone (even those staying inside the park at one of the hotels) must purchase an entry ticket in advance at the initial gate on the road in (or at Banrural locations such as Flores or Guatemala City). Note that tickets are no longer available anywhere inside the entry gate – that includes sunrise tour tickets. You purchase in advance and then use them as needed at the time/day of your choice.
Seeing the sunrise from Templo IV at the west end of the main site is possible from about October to March, but to enter the park before or after visiting hours you must purchase an additional ticket for Q100, as this is not covered in the normal park entry. You must also have a guide.
The core of the ancient city takes up about 16 sq km, with more than 6000 structures, to which an additional 4000 have recently been identified by LIDAR technology, making this one of the largest Maya cities ever discovered. To visit all the major building complexes, you must walk at least 10km, so wear comfortable shoes with good rubber treads that grip well. The ruins here can be slick from rain and organic material, especially during the wet season. Bring plenty of water, as you'll be walking around all day in the heat.
Please don't feed the coatis (pisotes) that wander about the site.