It is one of the main reserves of the Atlantic shrub (a short, branchy and woody plant) in Brazil, located at the Isla Grande, in the southern borders of the state of Rio de Janeiro.

Two areas of preservation where created within the island with the objective of protecting its unique natural riches: the Isla Grande and the Provincial Biological Reserve of the Southern Beach.

These are ecosystems covered with mangroves, necks of sandy or rocky grounds under shallow water, and short, intricate, dense vegetation.

The 3,600 hectares biological reserve occupies one third of the island and is the subject matter of diverse scientific investigations; it is besieged by tourists captivated by its astounding landscapes.

Human remains found here revealed they were 3,000 years old according to tests run with carbon 14. The warrior tribes of the Tupinambs and the Tamoios ruled the region when the first Portuguese arrived to the area. The leader of the former, called Cunhambebe, spread terror amongst the colonizers as he used to behead the Europeans intruders.

The zone was also a pirates hideout during those daysl, and many of them ended up settling in the region.

The tourists will find remains of the facilities and homes of the whale hunters, an activity whose peak lasted until the second half of the XIX century only.

A small town worth visiting is the village of Aventurro, built by the descendants of the old whale hunters who formed families with the local natives.

One of the best preserved mangroves of the State of Rio de Janeiro is held in the reserve. The Capivari River cleaves through a territory that has been altered by the interference (some times desired, sometimes not) of the people.