Make sure you purchase your Angkor Pass only at the official APSARA ticket office (map) just off the highway from Siem Reap a couple of kilometers from the southern park entrance.
Be sure to get to the temples early. You can enter the park beginning at 05:00; the temples open at sunrise. There are fewer visitors early in the morning, and the sun isn’t at full force. Arriving at the temples at 08:00 instead of 09:00 can make all the difference in staying one step ahead of the crowds.
Angkor is hot and sticky throughout the year, but the peak season is November to February, when the weather is dry and temperatures are coolest (25-30°C). The flip side is that the temples are packed, especially around Christmas and New Year’s, and hotel rates are at their highest. March to May is brutally hot, with temperatures reaching 40°C.
June to October is the rainy season, and outlying temples and the roads leading to them can turn into quagmires of mud. However, this is also when the temples are at their quietest, and it’s still often possible to do a good half-day round of sightseeing before the rains start in the afternoon.
The name *Siem Reap literally means “Siam Defeated”. These days, however, the only rampaging hordes are the tourists heading to the Angkor Archaeological Park.