On Gran Canaria in the Canary Islands, there is good snorkeling off Playa Meloneras since it is a rockier beach. The Playa Meloneras is known to be popular with fishermen so exercise care when snorkeling. You'll most likely encounter plenty of parrotfish. This snorkeling spot is more sheltered than the nearby Playa Maspalomas.
Since the Canary Islands are actually part of Spain, the best way to fly to the islands is through an airport in Spain. There are flights to all of the main Canary Islands directly from one Spanish airport or another. Of course, Madrid offers the best connections. The Aeropuerto de Gran Canaria (LPA) is located southeast of Telde on the east coast of Gran Canaria. Presently, there are not direct flights from the USA to the Canary Islands. Once in the Canary Islands, the best way to go between islands is still by inter-island flights. There are some boat services that do go between the islands as well. TIP: For your safety, most of the Canary Island snorkeling dive sites require snorkelers to have a diver-down flag marker. The waters around the islands are very popular with windsurfers and boaters, which has resulted in some snorkeler deaths over the past few years.
Overall, Playa Meloneras is the 2nd most popular snorkel dive spot of all 39 snorkeling dives in Canary Islands.