Started out from Playa del Carmen at about 10AM.  It is a 2-3 hour drive
from Playa and then a a short 5-10 minute ferry ride to Holbox.

We stayed at Casa de las Tortugas www.holboxcasatortugas.com,  Rooms
were clean and failry nice.  Electidicty, running water (tho the temp
out of the hot tap may be the same as the cold.)  Each room has a
balcony and a hammock as well as bed(s),There is a small cafe on
premises for breakfast, beer, cold drinks, snacks, etc.

First night we went into town and ate at a place called Cueva del
Pirata.  It does not get a recommendation.  The service was abysmal, the
portions small, tho the food was good and they had a better wine
selection that one might expect on this isolate and island.

Next morning, boat left at 7AM for the almost 2 hour ride out to where
the whale sharks lurk. We ran into a pod of dolphins on the way and
watched them bow ride for a few minutes.  Finally got to the are of the
whale sharks.

The way they do this is the boat driver gets in the path of a shark and
2 snorkelers and a guide drop in the water in front of them and swim
with the shark for maybe 5-10 minutes.  Everyone on the boat got at
least 3 chances in the water.  Visibility is low (they would not be
there if it was high - they are feeding on the low viz) maybe 5-6 feet
so you can really see the shark until it is right on top of you.  Then
you see the head and eyes and a freight train of shark body moving past
you.

After about 1/2 hour we also spotted some mantas and some lucky people
got both mantas and whale sharks.  At one point there were 5 mantas and
10 sharks in the immediate area of the boat.

A little later, another pod of dolphins joined the party.

We noticed that there were small fish jumping ahead of the whale sharks
and on one of my times in the water I saw that there was a large school
of bar jacks swimming with the wahle shark. They also appeared to be
feeding.

ON the trip back we trolled off the back of the boat with hand lines.  I
landed a 25lb black grouper and another in the party landed a 35
pounder.  But the prize was the 30lb red snapper.

I left my fish for the crew as part of their tip.

Got back to the hotwl around 3 so it was a fairly long trip.

Dinner that night was at Viva Zapata which does get a recommendation.
Good food good service.

There is also a pizza joint on the square that does a wicked lobster and
shrimp pizza.

Most of the hotels on the island will arrange transportation from the
Cancun airport or from Playa but there are only a few more weeks when
the sharks will be there.

It is only snorkeling but IMO well worth the time.