the ilha do capão, or big cape island, is located in the region where the fresh rivers and streams born in the nearby 'maciço da pedra branca' meet the salty waters of the sepetiba bay and the atlantic ocean.

capão itself is a large trapezium-shaped mass of land, delimited on three sides by rivers and canals and on the western side by the sepetiba bay.

it is also on this side that the other important islands of this area are located.

the suruquai, bom jardim and ilha nova are close to ilha do capão, while ilha do cavado and ilha das baleias are located beyond them.