Tennant Creek to Alice Springs is 531km (330 miles). The major point of interest on this stretch of road is the Devil’s Marbles. The area is located near Wauchope, 114km south of Tennant Creek
It contains formations of naturally rounded and oval boulders called Karlu Karlu by the local Aborigines. The boulders are located in a traditional Aboriginal sacred site and are important to the local Aboriginal people. The Kaytetye people believe that the boulders are the eggs of the rainbow serpent. Over time, the ceremonies and stories related to the Devil’s Marbles have largely been lost, but the site is still very important to the tribe and may be considered to be among the oldest religious sites in the world.
The Reserve is accessible (by short pathways) all year round and has a network of pathways with information boards and a basic camping area. The Devil's Marbles are made of granite, which surfaced like a little geological island in the desert, surrounded by incredible amounts of sandstone. The granite is thought to have formed about 1.7 billion years ago as a result of the hardening of magma within the earth's crust.
Thick layers of sandstone on top of it put a lot of pressure on this granite. After the folding of the earth's crust, which led to the lifting of the granite, and the erosion of the sandstone, the granite came to surface. The pressure was gone which caused the granite to be able to expand; cracks formed, and it fell apart in big, square blocks. Subsequently they have become rounded through various forms of erosion.