Snorkeling vs. Scuba Diving | All About Iceland The Silfra Fissure in Southwest Iceland is considered one of the best snorkeling and diving spots on Earth. In fact, TripAdvisor rated snorkeling in Silfra Fissure as one of the top 5 activities in the world! If you’re looking for a casual snorkeling trip, or want to up the ante with some serious scuba diving, then you’ve come to the right place. But first you need to decide whether you’re a snorkeler…