Cozumel to Chichen Itza

For those of you wondering what Chichen Itza is, here is a link:

http://en.wikipedia.org/wiki/Chichen_Itza

They are Mayan ruins.  Some of the people in our group debated on going here when we are in Cozumel.  Our ship will dock in Cozumel at 10 a.m. and leave at 7:00 p.m.

From all that I have read in discussion forums, a trip from Cozumel to Chichen Itza is a full day trip ad is not really recommended as a "do on your own" type of trip.  If you were to be late getting back to port, the boat would leave without you. 

After many cruises, John and I are fans of saving a little bit of money and booking our own excursions, but in this case if Royal Caribbean offers a Chichen Itza excursion for our cruise, then I would book it through the cruise ship.  That way if you are running late, the boat would wait for you.

Anyway... 

I hope those of you interested in this are not too disappointed.