Enjoy spectacular views, experience a variety of habitats and see the Nanguluwur art site along this rugged 12 km loop walk over and around Burrunggui (Nourlangie). 12km Circuit. Allow 6 hours. The Barrk sandstone bushwalk has no formed path. The ground is rough in places and there are steep slopes.The bushwalk is marked with orange triangular markers placed in trees and on rocks.Lavender-flanked wrens flit around the shrubs and trees while peregrine falcons hunt from the thermals created by hot air rising from the rocks. Chestnut-quilled rock-pigeons unique to the stone country of Kakadu and Arnhem Land, are common here. These birds never stray far from the rocks and are conspicuous by the loud clapping of their wings.
The sandstone (helmeted) friarbird is often seen and easily recognised by the small casque on the top of its beak. While the white-lined honeyeater is difficult to see, its distinctive call is often heard in the forested gullies and gorges of the stone country.
Geologists estimate that between 1400 and 1800 million years ago vast sheets of coarse sand were deposited under long since vanished seas and lakes in this area. Since being exposed the sandstone that formed from this, the Kombolgie sandstone formation, has slowly worn away. Faults in the 400 metre thick Kombolgie sandstone have eroded into crevices, gullies, caves and gorges. During the age of the dinosaurs (140 million years ago) shallow seas spread across the area, eroding the sandstone into sea cliffs (now the Arnhem Land escarpment) and islands (outliers). Burrunggui (Nourlangie Rock) is at the southern tip of the Mt Brockman outlier.