Chichen Itza (chee-CHEN eet-SAH) has the distinction of being one of the New Seven World Wonders and that, and its' importance in the Mayan culture is the reason so many people flock here to see the site every single day of the year.

If you want to enjoy this attraction, you should arrive early, at 8 AM or so when they are opening the gates. There are several advantages to this:

the sun is low in the sky and the heat is still bearable
the guides are fresh and not sweaty-faced and exhausted
the pesky trinket vendors are still setting up their "one dollar" goods
the hordes haven't arrived from Cancun and the Mayan Riviera

When you arrive, notice the empty bus parking lot. Remember how it looks as it will be a different sight when you leave around 10-11 AM. Buy your tickets, one for the state government office that oversees the site and one for the federal government department that does the same. Chichen Itza is a cash cow for both and even in this day of internet and computers you have to purchase two separate tickets at two separate wickets from two sets of employees and then hand them to two separate sets of ticket takers a few feet away.

Touring the site should take you about an hour and a half, if you are moving at a moderate pace. Of course if you are really interested, you can spend most of the day here, taking it all in but the distraction of the vendors and the crowds will probably make you want to run away as quickly as possible.

Currently guides charge around 700 pesos (the last trip it was $750) for an hour and a half tour, beginning at the main entrance and ending at the Old Chichen portion of the site where you pay them and they will ask suggestively if you enjoyed the tour (subliminal tip request) so be prepared.