On the Carlos Ameghino Isthmus, through which the Valdés Peninsula is reached, lies the Isla de los Pájaros Provincial Reserve. Situated 800 meters from the San José Gulf, this protected area has been created with the aim of sheltering the colonies of sea and shore birds dwelling the island.
The San José Fort, founded by Juan de la Piedra in 1779 and destroyed by the Indians in 1810, used to be nestled in this area.
The quiet waters and the large tides, which present a 12-meter-high difference between the high and the low tide, join the island with solid ground. When the sea recedes, a narrow passage of sea bed becomes exposed. Access to the island through this passage was permitted until recently, but at present it may not be used due to the damage caused to the habitat.
The interpretation center has a glass dome with a very powerful telescope that enables visitors to observe the Nuevo and the San José Gulfs, and also offers a wide range of information about the diversity of wildlife in the peninsula.