The Devils Marbles are located close to the Stuart Highway (the road between Darwin in the upper north and Melbourne in the south of Australia). It’s a sacred site to aboriginals
From http://www.outback-australia-travel-secrets.com/devils-marbles.html:
In the Aboriginal mythology the Devils Marbles are the eggs of the rainbow serpent, and many “dreamtime” stories and traditions of the Warumungu, Kaytetye and Alyawarre Aboriginal people are linked with this area. It has a deep spiritual meaning for both men and women (Aboriginal cultural sites are often specifically for either men or women.)
This place was simply incredible. It was nice weather when we got there and the sunshine made the marbles look extraordinairy. A nice anecdote btw: in the nighttime I wanted to go to the toilet, but the friend I was with told me that the toilet nearby was very dirty. So I decided to go to another toilet a couple of hundred meters away. But soon I got the feeling I was followed. I had a torchlight with me and when I look back, I looked straight into the face of a dingo. So I turned around lol