The gigantic boulders in precarious piles beside the Stuart Hwy, 105km south of Tennant Creek, are called the Devil's Marbles. Karlu Karlu is their Warumungu name, and this registered sacred site has great cultural importance. The rocks are believed to be the eggs of the Rainbow Serpent.
A 15-minute walk loops around the main site. This geological phenomenon is particularly beautiful at sunrise and sunset, when these oddballs glow warmly. The camping ground has remarkably hard ground, pit toilets and fireplaces (BYO firewood).
At Wauchope (war-kup), 10km south of the Devil's Marbles, you will find the Wauchope Hotel. Budget rooms are dongas (small, transportable buildings); the costlier rooms are more spacious, with bathrooms. Meals from the restaurant are more than satisfactory.
At the kooky Wycliffe Well Roadhouse & Holiday Park, 17km south of Wauchope, you can fill up with fuel and food (mains $15 to $25) or stay and spot UFOs that apparently fly over with astonishing regularity. The place is decorated with alien figures and UFO newspaper clippings. The park has a grassy campground, an indoor pool, a kids' playground, a cafe and a range of international beer.
Heading south, you reach the rustic Barrow Creek Hotel, one of the highway's eccentric outback pubs. In the tradition of shearers who'd write their name on a banknote and pin it to the wall to ensure they could afford a drink when next they passed through, travellers continue to leave notes and photos. Food and fuel are available and next door is one of the original Telegraph Stations on the Overland Telegraph Line.
In the grand Australian tradition of building very big things by the side of the road to entice drivers to pul up, Aileron, 135km north of Alice, has Naked Charlie Quartpot, the 12m Anmatjere (Anmatyerre) man. Charlie cuts a fine figure at the back of the local roadhouse, along with his larger-than-life family. The Homestead Art Gallery sells inexpensive paintings by the local Anmatjere community, as well as works from the Warlpiri community of Yuendumu.
About 70km north of Alice, the Plenty Hwy heads off to the east towards the Harts Range. The main reason to detour is to fossick in the gem fields about 78km east of the Stuart Hwy, which are well known for garnets and zircons. You're guaranteed to get lucky at the popular Gemtree Caravan Park. For a taste of desert life, time your visit with the annual Harts Range Races (in August), one of the Territory's best outback rodeos.