The place next door to Garaffon is Garrafon de Castilla, and it has a nice little restaurant/bar and some nice snorkeling for very reasonable prices. Garrafon is a bit garish, and makes you wear a PFD to snorkel, and last I looked charged $55 US to spend the day there. The buffet included for this price is pretty nice and includes drinks, and there is a lot of entertainment for the kids such as a zip line and sit on top kayaks (though they must remain within the roped area). Farralon is the small point with the lighthouse at the southern side of the bay where the ferry arrives, and is probably the best snorkeling on the island, but you have to book a boat to get there (again, not unreasonable prices). Swimming there from the main part of the island would be ridiculously unsafe given the heavy boat traffic. If you are staying at the Avalon reef club or Maya Kiin, there is cool little stuff all over the little bay described above. Last year I found an old dead coral head washed in by a storm in a foot or two of water that had a small green moray, a clown shrimp, a stone fish, and lots of small but colorful species of juveniles all within 4 feet of one another. I've also run into eagle rays at the end of the pier to the north from Avalon. Any distance from the shore, and you will encounter some potentially heavy current. I've done a little drift snorkeling on the north end of west (ocean) side of the island, but the current is heavy, there is a lot of private beach that would be impolite to cross, and you must be strong swimmer. The current at the south end of the island is also quite strong, and will take you away from land at times much faster than probably anyone can swim. Have good trip. I'm headed down in 5 days.