Hell is a wide spot in the road that has a postoffice, and a couple of tourist traps (gift shops). Supposedly there are some rock/coral formations that look like "Hell", (how they determined that is a mystery). There you can mail a post card from "Hell".
Michigan also has a Hell, if you want to cover all the bases.
We took an "island highlights" tour in Grand Cayman the first time we went, one of the stops was Hell. Although it was neat to look at for about 3 minutes, I wasnt overly impressed. You wouldnt be missing much if you didnt go, other than being able to say that you had been to Hell. (IMO)
Someone please correct me if I am wrong here, but if your snorkel trip ends at 12:30 island time, that is actually 1:30 ship time so it only sounds like you have 1/2 hour before you leave. Not really enough time to do anything. I would be more concerned about getting back to the ship on time!
Like I said, someone please correct me if I am doing the time change wrong!
We booked a snorkel trip with Captain Marvins and they also arranged a tour to hell, the turtle farm, seven mile beach and the Tortuga rum factory. We took the tour at 8:30 and the driver dropped us off at the dock where we left for the stingray city and snorkle trip at 10:30. We ended this trip at 12:30 and had a little time to walk around town and grab a bite to eat. We were on the 3:00 tender. Hell is just an area with black rocks and a gift shop. The reason you want to go is to send a postcard with a postmark from "hell" I am glad we took the tour, though, because our guide told us some information about the island.
I am back and didn't even try to go to hell. I had so much fun with the sotos gang on our three stop stingray snorkel tour, I forgot all about hell. So, I just stopped at the shops and bought a cuban. Jeez for someone who does not smoke, It was pretty good. Head buzz too...
I wouldn't worry about missing hell its a silly little tourist trap. My husband purchased postcards when we were there. He mailed them to friends and family at their postoffice. We were back from cruise weeks and weeks later before anyone got their postcards. Everyone liked my litte rumcake presents better
Glad you had a good time.