Around 30 years ago, Jacques-André Istel turned to his wife, Felicia Lee, and said, “We’re going to sit in the desert and think of something to do.”

Hardly an enticing proposition, but by then, Lee was surely used to her husband’s hare-brained schemes.

If I told her tomorrow we were going to Mars, she would say, ‘What do I pack?’

In 1971, at great risk to himself and his then bride-to-be, Istel piloted the couple on a round-the-world flight in a tiny, twin-engine plane that had hardly the oomph of a Chevrolet automobile. Before that, there was the whole business of convincing people to jump out of planes: in the 1950s, after returning home from the Korean War, where he served with the US Marines, Istel developed parachuting equipment and techniques that made it possible for the average Joe to leap out of an airplane at 2,500ft and land as if having tumbled from a 4ft bookcase. Soon, Americans by the thousands were enjoying the latest craze: skydiving.

Lee was a reporter for Sports Illustrated– she met Istel, by then known as ‘the father of American sport parachuting’, during an interview for a piece in the magazine – and had her own taste for adventure. “If I told her tomorrow we were going to Mars, she would say, ‘What do I pack?’,” Istel said.

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And so, in the 1980s, the couple moved to the far south-east corner of California, a few miles west of Yuma, Arizona, off Interstate 8, where Istel had acquired a 2,600-acre parcel of land several decades earlier. Apart from a good aquifer, this particular patch of the Sonoran Desert had little to recommend it. But “we realised that we loved it – the calm, the beauty,” Istel said.

With nothing much around apart from an RV park and some impressively tall sand dunes, the couple’s desert refuge was pretty much in the middle of nowhere. So it made sense, at least in Istel’s fervid imagination, to put it in the middle of somewhere. In 1985, the French-born parachuting pioneer cajoled California’s Imperial County Board of Supervisors into designating a spot on his property as The Official Centre of the World. (Audacious, perhaps, but not necessarily inaccurate, given that anywhere on the Earth’s surface could be the centre.)

A landmark of such importance needed a town of its own. The following year, Istel created Felicity, which now boasts about 15 residents and its own freeway sign. Facing no opposition, Istel got himself elected mayor that same year – apparently for life.

But Istel wasn’t done with his Xanadu in the desert. He had an idea to build a granite monument with inscriptions honouring people and places important in his life – fellow parachutists, his alma mater (Princeton University in New Jersey), and his family, who had fled France during World War Two and settled in New York. His father, André, had been an advisor to Charles de Gaulle, and his mother, Yvonne, was a wartime volunteer.

Istel didn’t want just any monument. It had to be magnificent and, more importantly, it had to be something that would last far, far into the future. He hired structural engineers who came up with a design for an elongated, granite triangle that just might – “short of the planet blowing up,” Istel said – survive to the year 6000.

The triangular monument went up in 1991; it was 100ft long, about 4.5ft high, and faced with some 60 panels of polished, red granite. The durability came from what was inside: steel-reinforced concrete sunk into trenches 3ft deep.

It's where Martians will come to learn about humanity

Istel then decided he would build another monument, this one to honour US marines who fought and died in the Korean War. Then came a third monument, and a fourth, and a fifth. Today, 20 granite monuments, arranged at artful angles across the desert floor, collectively make up The Museum of History in Granite, a sort of open-air bank of knowledge for the ages. As a visitor posted on TripAdvisor, the museum is where “Martians will come to learn about humanity”.

Istel has engraved his stone triangles with tidy distillations of much of what we know about the world, from the Big Bang to former US president Barack Obama. Visitors – and they come by the thousands each year – learn about Hinduism, the eruption of Vesuvius, the Zapotecs of central Mexico, Buddhism, the birth of Jesus, Attila the Hun, Pythagoras' theorem, the behaviour of the walrus, Greek philosophy, the Gettysburg Address, the Moon landing and terrorism in contemporary times.

Despite his Ivy League background, Istel believes strongly that self-acquired knowledge “is probably the best form of education”. The idea behind these thumbnail sketches of history is to offer just enough information to whet the reader’s appetite. Most topics – even big ones – get at most a couple hundred words.

Lee handles most of the research, using reputable publishers like Oxford, Britannica and Larousse. Istel writes the text, then he and Lee go back and forth on the wording before settling on a final version. An entry titled ‘Interesting Times’ went through 59 drafts. Once the text is ready, professional engravers get to work, often toiling in the glow of lamplight under a night sky to escape the brutal desert heat. To accompany the text, artists etch illustrations into the hard stone panels.

The museum can’t cover everything, so “you pick and choose things that are interesting,” Istel said. He often groups related items into a single theme. The Code of Hammurabi and the Ten Commandments appear under ‘Early Concepts of Law’. The American concept of ‘Manifest Destiny’ is mentioned on a panel called ‘Exploring and Expanding’, along with the expedition of Meriwether Lewis and William Clark. Some topics are of personal interest to Istel – parachuting gets ample space – while other topics come as suggestions from others. Lee came up with the idea for a panel on the ‘Great Seal of the United States’, the US’ official coat of arms.

Some of the inscriptions are amusing, if little more. For example, in 1809, US president James Madison proposed a cabinet post of Secretary of Beer. Hamburgers “account for nearly 60% of all sandwiches eaten”. The grizzly in California’s original Bear Republic flag “looked more like a pig than a bear”. The typical Wild West cowboy was “frequently hundreds of miles from the nearest bar or woman”. The TV mute button, which Istel considers “one of the world’s great inventions”, gets a mention.

Istel aims for objectivity and is a stickler for accuracy. But given that even reputable sources will disagree on certain points, it’s a difficult challenge. “The answer is, you do the best you can,” Istel said.

The museum’s official season runs during the cooler months. From the day after Thanksgiving (the fourth Thursday in November) through the end of March, visitors can join a 15-minute tour led by a volunteer docent, watch a short video about the museum or grab a bite at the small restaurant. During the rest of the year, the museum is open, but only for self-guided tours.

Istel’s property is also dotted with pieces of art and architecture that seemingly have little to do with anything, but add a bit of absurdist fun. A 25ft section of the original spiral staircase from the Eiffel Tower rises incongruously into the desert sky. A bronze sculptural replica of Michelangelo’s ‘Arm of God’, from the painting on the ceiling of the Sistine Chapel, acts as the gnomon of a sundial.

There is also a hollow, 21ft pink-granite pyramid, inside which is a metal plaque that marks the centre of the world. A $2 fee, on top of the museum’s regular admission of $3 per person, entitles visitors to a certificate attesting to having stood on the exact spot.

The tallest and most striking element on the property is a little white chapel that sits poetically atop a 35ft earthen hill. Istel is not particularly religious, but he thought it fitting to install the chapel if for no other reason than to “keep us on our good behaviour”.

Istel and Lee live alongside the museum in a lovely, light-filled house with big windows that look out on chocolate-coloured mountains. There’s a library stocked with leather-bound volumes and a piano that Lee plays. Istel serves guests fizzy water – wine if they prefer – in crystal glasses.

Istel has made plans in his estate for the museum and all that surrounds it. Yet – as he approaches his 90th birthday – he has no plans of slowing down.

The museum is far from complete. Dozens of blank granite panels await text and illustrations. There is also a new freeway sign to be installed, and the never-ending task of keeping up with online reviews. Istel responds to each – even the mean ones – with unfailing politeness.

May distant descendants, perhaps far from planet Earth, view our collective history with understanding and affection

If residents of other worlds do indeed visit the museum one day, Istel would not be particularly surprised. He believes that humans will one day colonise other planets and eventually stars, so it’s not inconceivable that they could, at some point, return to Earth. One granite panel bears a big question mark, along with this inscription:

“May distant descendants, perhaps far from planet Earth, view our collective history with understanding and affection.”

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