Nullarbor National Park and Regional Reserve covers 2,873,000 hectares and protects part of the world's largest semi-arid karst (caves) landscapes. The Nullarbor Plain (Nullus Arbor meaning no trees) extends north from the Eyre Highway up to the Transcontinental Railway Line and west in Western Australia.

This area supports an extensive network of dolines (sinkholes), blowholes, caves and underground caverns that have been created over thousands of years by water dissolving and eroding the layers of limestone. Many caves contain sensitive and important scientific and cultural features such as paintings and fossils. Permission is required to enter the majority of caves in the region, however several caves do allow public access or viewing from the surface.

The park supports a diverse array of plants and animals including dingos, Australian Bustards, kangaroos and one of the largest populations of Southern Hairy-nosed Wombats.

Access tracks within Nullarbor National Park and Regional Reserve are limited and visitors venturing off the highway should be well prepared for outback travel and carry sufficient food, water and fuel supplies for the trip.

The southern boundary of the park where the Nullarbor meets the Southern Ocean is one of the most distinctive features of the park. Eighty metre-high cliffs stretch for 200 kilometres along this unique coastline providing spectacular views.

Southern Right Whales gather at the head of bight in this area to give birth. At times up to 80 whales (including newborn calves) may be seen from the viewing areas provided.