So we hired the driver to take us from GIG to the Ilha Grande ferry and I think that was the right call. With GPS, I think I could have done the drive, but it might not have been that pleasant. The roads seemed a little confusing in the Rio area. There are also a crazy number of speed cameras on the route (many of them not very intuitive) that my driver would slow down for. Not sure what happens to foreigners who get tickets! I also thought the ferry pier was quite hidden at Conceição de Jacareí (turn left at the big petrol station, go to the water, and turn left again -- there are several small parking lots), and I'm glad I didn't have to figure that all out without being a Portuguese speaker. The ferry piers were quiet mid week, but somewhat chaotic on Sunday evening. There were even fist fights at Conceição de Jacareí (which the driver attributed to visiting favela residents) when we returned; I was glad to have a driver guide me through the melee.