In other parts of the world, Boia Cross is called "floating down the river in a inner-tube." Ecodunas offers a half-day float. The trip there and back is 90 minutes each way, and you spend 2 hours floating downstream. Cost is R$50 per person.
Note: This information was accurate when it was published, but can change without notice. Please be sure to confirm all rates and details directly with the companies in question before planning your trip.