The islands are part of the Islas del Ibicuy Department and have scattered but important settlements, like their capital Villa Paranacito.
They built embankments of sand and earth as look-outs and flood defences known as cerritos, which can still be seen rising above the dense vegetation which characterises the river delta.
It is thought that the Guaraní arrived in Ibicuy in search of the tierra sin mal, the earthly paradise inhabited by the spirit Ñandey, located in the east close to the sea.
The marxist Liborio Justo lived there in the 1940s, the harsh environment and the fugitives who inhabited it, inspired his book of short stories, entitled Rio Abajo ("Down the River"), which was later made into a movie with the same title.
Nowadays tourism is one of the main activities of the islands, where typical Delta wildlife such as the Neotropic cormorant, capybara and marsh deer can be seen.