there are plenty of tour boat companies in rio de janeiro, mostly located in the marina da glória, near the center of rio and just about 15 minutes by taxi from the zona sul, and also easily reachable by bus.

most tours allow for a peak into many interesting part of the bay, such as niterói, flamengo, the morro da urca, the sugar loaf, praia vermelha, and praia de fora - the place where the city of rio was founded.

the companies offering tours to the islands vary in route and ships, ranging from a world-war one ship to sail boats, yachts, and speed-boats - depending on the tour, food and drinks are served onboard, and it is possible to go swimming for a while near the islands

on this link we posted some pictures of a tour we took on a tour boat to the cagarras islands, and the great views that can be enjoyed from there.