Pantanal, one of the largest wetlands in the world, is located in southwest Brazil, close to the bolivian and paraguayan borders. It is a remote location, and arranging tours can be a real adventure by itself. There is a big offer but also many complains so you don't know which operator to choose; I didn't want to repeat the Uyuni experience. The safest was to take that what other travelers just completed and were satisfied. The HI Hostel in Bonito helped by having a travel arrangements desk onsite.