The area is thickly forested and has high rainfall, especially on the west-facing slopes but less so on the sheltered eastern side, which has golden sand beaches.

Natural features of the region include: the limestone Pancake Rocks near the town of Punakaiki on the edge of Paparoa National Park; Farewell Spit at the north of the island, the longest sandspit in New Zealand; the nearby Te Waikoropupu Springs; and the karst areas on the flanks of Mount Owen (New Zealand) in Kahurangi National Park.

There are small areas of northern rata (Metrosideros robusta), rimu, and miro rainforest hardwoods as well as karaka (Corynocarpus laevigatus) and the Nīkau palm (Rhopalostylis sapida) near the coast.

In the less fertile rocks areas there are yellow pine (Halocarpus biformis) and Dracophyllums including the endemic D. townsonii and the mountain neinei (D. traversii).

The alpine plants found here including Celmisia dallii occur as these peaks, along with Fiordland at the southern end of the island, were a high-elevation refuge from the effects of the last ice age.