What's eight times the size of Uluru but can fly under the radar?
It might sound like a trick question, but the answer is Wilpena Pound in South Australia's Flinders Ranges.
Most people have never heard of this arresting crater-like rock formation, which was last year voted Australia's second best travel secret out of a list of 100.
And part of the reason Wilpena doesn't have the same profile as Australia's famous red rock is the distance you have to travel to get there.
It's 429km north of Adelaide, which is often described as "just" a 4.5-hour drive.
While the scenic route does takes you through South Australia's beautiful Clare Valley wine country, most of the trip is spent traversing semi-arid plains stretching as far as the eye can see.
On the road you'll see throngs of kangaroos, emus and wallaroos roaming the red earth looking for water.
And nothing compares to the sweet, crisp taste of your first glass of wine or schooner of South Australian beer when you arrive.
But we're not here for the semillon or the pale ale, although they are noble companions.
It's to see the mother of all Australian rock basins.
Big enough to fit eight Ulurus inside it, Wilpena Pound covers nearly 8,000 hectares in the most northern point of the Flinders Ranges National Park.
Ideal for bushwalking, the pound itself is 11km long and 5km wide.
To put it in perspective, that's the length of 220 Olympic-size swimming pools, and you'd have to swim the equivalent of 100 laps to get across it.
There are plenty of trails ranging from easy to challenging if you're on the hunt for the best lookout, but don't feel obliged to walk them all.
Temperatures here can exceed 40C in summer, something to keep in mind if tackling the full-day return trek of Wilpena's highest point, St Mary Peak, at 1170m above sea level.
Down on the ground, Wilpena looks like a rocky low mountain range, its rust-coloured quartzite and limestone walls rising 200 metres out of the vast landscape.
But the best views are bird's eye, looking down into the naturally formed amphitheatre. It's from the window of a Cessna aircraft that you realise the bowl is actually a flat plain with a rim formed by the rugged hills surrounding it.
In the local Aboriginal dialect Wilpena roughly translates to "cupped hand" or "a place where fingers bend", while white settlers thought it resembled an enclosed cattle pound and attempted to use it as such.
Take a closer look at this geological bowl and you'll find sedimentary layers from 800 million years ago containing fossils of the multi-celled organisms that existed before they evolved and grew skeletons.
It is the first clear evidence of this kind in the world.
So on top of being an impressive-looking rock, Wilpena also gets kudos from the scientific community.
Whether it remains a little-known travel secret or Australia's next tourist hot spot, Wilpena's charm is unique.
Its isolation and contrast to the surrounding countryside will surprise and enthral adventurous explorers unafraid of venturing out into age-old lands in search of a new experience.
IF YOU GO
GETTING THERE: Within Australia, Qantas, Virgin Australia, Jet Star, and Tiger Air fly to Adelaide from most major cities.
Internationally, Qantas, Air New Zealand, Cathay Pacific, Malaysia Airlines, Air Asia, Singapore Airlines and Emirates all fly into Adelaide.
You can drive, catch a bus, or charter a plane from Adelaide to Wilpena Pound. If driving, aim to get there by sundown. Insurance companies won't cover vehicles driven on country roads between dusk and dawn when the risk of hitting wildlife is high.
STAYING THERE: Wilpena Pound Resort has 60 rooms, a campground, and a new luxury safari camp with 15 tents (www.wilpenapound.com.au)
PLAYING THERE: Air Wilpena scenic flights are priced from $165 per adult. Photography enthusiasts can request special flights where a window is removed for your shooting pleasure (www.airwilpena.com.au)
Bushwalks and guided 4WD tours are the easiest way to see the countryside.
Every year in February, the Royal Flying Doctors Service holds a black tie fundraising dinner at the basin called Wilpena Under the Stars (www.flyingdoctor.org.au)
* The writer was a guest of the South Australian Tourism Commission.
