Western Australia: Dune roamin'

The Pinnacles Desert in Nambung National Park is home to thousands of limestone pillars. Photo / WATC

You know the ride is about to get interesting when the driver stops to let the air out of the tyres.

"Bus" isn't really the right word though - think sturdy four-wheel-drive truck, fitted out like a luxury coach for 20-odd people.

And we're about to discover the reason for the big, soft tyres and seatbelts: an off-road adventure across 6km of towering sand dunes.

Lancelin, about 90 minutes' drive north of Perth in Western Australia, is a tiny town with a lot of sand.

The dunes are 6km long and 1km wide, twice as high as the truck.

Bus driver Rob from Australian Pinnacle Tours barrels along at surprising speed as he scouts for a suitable dune. Then it's a slow chug up the slope, a pause at the crest, and a plunge down the near-vertical face.

It feels pretty safe strapped in the back, but still not the kind of thing you'd like to experience on Auckland's inner-city Link bus.

The dunes are constantly shifting and being re-formed by the winds blasting off the Indian Ocean. Come back tomorrow, Rob says, and you'll find a whole new landscape.

The next part of the sandy adventure is even more thrilling: sand-duning.

We pile out of the bus, wax our sand-boards, and hurtle down the slope with peals of delight. If it wasn't such hard work climbing back up the soft, boggy dune again, I could do this all day.

My day-trip north of Perth also took in the Pinnacles Desert in the Nambung National Park. Here, thousands of limestone pillars rise up to 3m out of the sand.

Scientists are still arguing about how they formed; visitors content themselves with finding funny-shaped ones.

My guide's handy at finding picture-worthy pinnacles, but not so good on the wildlife: "Bugger me if I know what that is," he says, as a mysterious reptile scuttles by.

This part of Western Australia features remarkable countryside. Tiny townships cluster around stunning white sand beaches and glassy blue-green water. The land runs almost dead flat from the coast to the Darling Ranges, and yet the surprising thing is how much it changes: from the parched north coast to the pretty, riverside state capital, and further south to flourishing vineyards and the rugged coastline of Cape Leeuwin.

Also south is Margaret River, Western Australia's newest wine region. Grapes were planted here in the Swan Valley in the 1830s, but weren't grown alongside the Margaret River until the 1970s.