The waters around the Búzios peninsula offer decent diving by Brazilian standards, with visibility that routinely reaches 10–15 metres and water temperatures warm enough for a 3mm wetsuit outside the cooler winter months. The main attraction is marine life rather than dramatic topography: reef fish, moray eels, octopus, sea turtles, and the occasional school of larger fish around the deeper rocky outcrops.
Several dive operators work out of Búzios, most located near João Fernandes beach or in the town centre. The most popular dive sites are Ilha Feia, Ilha Rasa, and various rocky formations along the northern coast. These are accessible only by boat.
For snorkellers, the rocky ends of Tartaruga, João Fernandinho, and Azeda beaches offer the most interesting conditions without equipment or a dive guide. Water shoes are useful as entry over rocks can be slippery.
PADI-certified courses are available for beginners through local operators. Prices are reasonable by international standards.