Tocantins is one of the states of Brazil. The state was formed in 1988 out of the northern part of Goias, and construction began on the capital, Palmas, in 1989, in contrast to most of the other cities in the state which date back to the Portuguese colonial period. It is the newest Brazilian state and, because it is still very young, it is developing slowly, building on its most important resources: the rivers Araguaia and Tocantins, the largest hydro basin entirely inside Brazilian territory. Because it is in the central zone of the country, it has characteristics of the Amazon, but also has open pastures. The Ilha do Bananal, in the southwest of the State, is the largest fluvial island in the World.