The tiny beach of Aripeba is nature's extravaganza.
With thick, dense Atlantic rainforest falling all over it and warm, calm, emerald waters, is ideal for swimming and snorkeling. So wild that you'd almost expect to see Tarzan, Jane and Cheeta showing up any minute for a bath.
Well, provably I'm exagerating a bit.
Found the place a little bit too crowded to suit Tarzan's lifestyle (and definitely mine) but it was a very nice experience nevertheless.
It would also have benefited from a bit more of cleanness as well. Litter is perhaps the biggest challenge Ilha Grande has to face due to the large number of visitors on a yearly basis.
So if you are a predator, please stay away - nobody needs you there - nature least of all.
There are several tour operators along Rua da Praia (in Abraćo) that can take you there, either by escuna (schooner) or a fast boat. Ask first because options vary, along with prices. Standard is around 35 Reais for a escuna ride, not counting lunch at Japariz or somewhere else.
In all cases, you will visit other beaches as part of your day-long excursion - 10 to 4pm or so - it could be Lagoa Verde and Lagoa Azul, Saco de Seu (don't miss it) and provably Freguesķa de Santana as well, first settlement in Ilha Grande.
It has the oldest (Imperial) palm trees and a church of Colonial Portuguese style built by slaves in 1796.