Carlisle Bay is a roped off area so there is no boat traffic.  The main attraction  are 8 wrecks sunk in the bay.  Lots of different sea life.  Depth is under 60 feet so good bottom times as well.  At the pavilion are many benches to lay gear out and suit up.  Leave nothing on the benches alone while you dive.  It is about a 20 yard walk from the benches to the waters edge.  If you have non-divers with you,  the beach there is very nice too and they can work on their tan.

On the West side of the island, from Oistins, drive north on the main highway with the ocean to your left.  Go past Mojo's Bar, past the Opa restaurant, past St. Ann's Barracks and stop when you see on the left a large blue pavilion (shaped like a gazebo).  Directly across the street is the Prime Minister's Office.  You can park in a lot just before the pavilion....but be aware to get into the parking lot you have to drive over the curb.

Carlisle Bay

I followed the advice from this site, and went snorkeling from the shore out towards the wrecks in the buoyed off area.  They are quite easy to spot as this is where all the tour boats stopped.  I'm not a particularly experience snorkeler - its about the 7th time I've done it.  I did find it quite fun swimming out over the shipwrecks, although on the way back it was quite difficult getting through the surf when you're a bit tired.  The visibility wasn't great from the surface, you could see all the way to the bottom but it was a little hazy.  I did dive down a couple of times and the photos I took then were much better.  There were a lot of different types of fish.

Neil Heyes's Dive Log

@neil_heyes

1 dives