I visited Cancun in 1996. There I obtained my PADI Open Water Diver certification with Aqua World. I did several boat dives in nearby reefs and I also took one of their snorkeling trips. The dive operation was very professional and the dives where ok. The highlight of the dives was seeing a nurse shark which is not too spectacular for a dive in the area, it is still fairly interesting considering that they where OWD training dives.