We took the mountain bike ride to the Cenote to snorkel. It was 97 degrees and bikes were not well maintained. Two did not finish the tour. I had wanted to see the cenotes for a long time so it was still worth the money. They stop at a tiny Mayan town and the locals fed us after the swimming. I love local color and this part was terrific.
What can I say about diving in Cozumel..If you have never done it you must add it to your list. We did not take our own gear so we arranged for gear as a part of the package. We are accustomed to integrated BCs and computers, that is not what was available. But any dive in Cozumel is a good dive.