As part of the Magallanes Sub-Polar (or Sub-Antarctic) Evergreen Rainforest, UNESCO highlights the area’s "mosaic of contrasting ecosystems and unique and singular characteristics on a world level.

The park is named after one of the most important Salesian priests in Chilean history, Father Alberto Maria De Agostini.

Fuegian peoples include the Selk'nam, Haush, Manek'enk and Yaghan), the latter settling the lands along the channel approximately 10,000 years ago.

This pristine coastal ecosystem is home to various species of trees such as the coihue (nothofagus betuloides) and canelo (drimys winteri).

Mammals found in the park include the Culpeo or Andean fox (lycalopex culpaeus), the South American gray fox (lycalopex griseus), also known as the Patagonian fox, the marine otter (lontra felina), known locally as chungungo, the South American sea lion, the southern elephant seals, the leopard seal (hydrurga leptonyx), the Chilean dolphin (cephalorhynchus eutropia, also known as the black dolphin or tonina), the Burmeister's porpoise (phocoena spinipinnis), Peale's dolphin (Sagmatias australis), the humpback whale (megaptera novaeangliae), and the guanaco (lama guanicoe).

There are no roads to the park, and as such, most visitors arrive by cruise ships or other boats, generally from Punta Arenas, or else by aeroplane from Puerto Williams.