Inside Kate and William's mystery holiday Greek island: As Royals said to have been spotted off the coast, what they would have seen, done... and why it's perfect for little Princes and Princesses

No Ryanair scratchcards for William or €7 (£6) cans of Jack Daniel’s and Coke for Kate this summer.

Because while so many of us arrive on Kefalonia by budget airline, the Prince and Princess of Wales touched down by private jet a fortnight ago.

So began their getaway on the gorgeous Greek island, perhaps the best of them all for a family - and I should know, having recently come back from one myself. Kefalonia with the kids, I can confirm, is perfect: pretty, sleepy, beachy.

The Waleses took George, Charlotte and Louis with them, of course, but also rumoured to be with them were Michael and Carole Middleton. No room, it seemed, for the kids’ other more illustrious granny and granddad (and not much chance of their first cousins putting in an appearance).

Upon landing, the royal party was whisked away in a convoy of vehicles with tinted windows. On our visit, it was somewhat different: on arrival at Argostoli airport we were greeted by a beamingly friendly one-man car hire company who charged a pittance for a week, and wouldn’t even accept a tip.

That proved typical of the islanders’ filoxenia, which translates from Greek to ‘love of strangers’, and shows itself in a natural instinct for hospitality that’s lasted through the millennia. Wherever we went, locals would take the time to tell us about their favourite secret beaches, enthusiastically scrawling directions on scraps of paper.

It possibly helped that we went out of peak season (last October half-term). Beaches were empty and villages so quiet you could hear goat bells tinkling in the fields. Taverna waiters shruggingly invited us to choose whichever table we fancied as they were all free.

Meanwhile, the weather was wonderful. The Hades-high heat of summer had mellowed, but it stayed t-shirt temperature all the way till bedtime.

Even in July, though, the future king and queen will have relished the calm and quiet. Argostoli, the island’s capital, has some great restaurants (menu tip: order anything with tentacles) and a lovely laidback café scene. The pace is more pootle than bustle.

We stayed at the chic, cheap Kefalonia Grand hotel, and even with our balcony doors wide open on to the town’s main drag - and its handsome, working natural harbour - we slept utterly undisturbed. Beyond, the island unfurled in a gently rolling wave of bougainvillea-bedecked, whitewashed villages surrounded by lovely gnarled old olive orchards.

The most appealing towns are the old fishing (now yachting) community of Fiskardo, in the island’s far north, and Assos, where houses in pencil-case colours tumble down a tree-shaded slope towards a delicious sliver of beach. But there are satisfyingly few must-see sights on Kefalonia, and its handful of monasteries and 16th-century fortresses didn’t distract the royals. ‘Dad, castles are boring!’ I like to imagine their kids chorusing, ‘Plus we live in the grounds of one.’

In fact, a spot Their Royal Highnesses are thought to have visited is Melissani Cave, a supernatural-looking sinkhole where sunlight pours through the earthquake-broken rock roof onto an underground lake. That may not sound much, but visit around midday and you’ll find the water an exquisite aquamarine, as if all the sapphires, emeralds and diamonds of George’s future crown had been combined (with a few jades and turquoises thrown in to glow things up a bit).

Boatmen glide visitors around it for a few minutes, retelling its history (ancient), legends (fun) and the story of its discovery (bit boring). The Waleses, or their security detail, are rumoured to have had the place closed for their visit, but when I took my kids there a Greek couple in our boat insisted on feeding them chocolates the whole time - the kind of filoxenia even an 11 and 13-year-old can (and did) appreciate.

Kefalonia’s own crown jewels, however, are its beaches. Every corner and cove on the island seems to be edged with a crescent of either soft sand or pretty pebbles for the sea to sssshhh soothingly over - and the water is almost the same neon-blue-green as at Melissani.

The most famously photogenic strand is Myrtos in the north, but Antisamos has its fans too. Both upstaged Nicolas Cage and Penélope Cruz in the 2001 film Captain Corelli’s Mandolin, set and shot on the island.

Our favourite beach was a lesser-known lovely, local secret recommended by a waiter. ‘Insisted on’ is probably closer to the mark. I fell for Paralia Petani before we even got there: hairpinning the hire car up and down the mountain roads towards Kefalonia’s quieter west coast, with slightly maudlin Greek music on the radio, was a pleasure in itself.

Read More

The kids loved looking for turtles from the deck of the little ferry that carried us and the car back across the bay to Argostoli come evening. After dark, those unlit hairpins would have been... hair-raising.

In between, we lorded it up on an echoingly empty slice of sigh-inducingly cyan water. With a mile or so of beach with just us on it, we felt like royalty ourselves.

Actual blue-bloods don’t bother with hotels; Wills and Kate and Co. are reported to have borrowed a $40million superyacht called Almax for their trip.

But there are some princely digs on Kefalonia. After Argostoli, I took my own heirs off to Eliamos on the island’s southern shore. This Relais & Chateaux hotel is made up of a dozen decorous little villas dotted around a gorgeous hillside garden, each one with sliding glass walls opening on to terraces and private pools with sunrise views across the Ionian Sea.

It’s a classically understated, unglitzy slice of Kefalonia, but you should consider going there sooner rather than later if that’s what you’re seeking.

Just a day or two after the HRHs, the island hosted another globally-recognised name: princess of reality TV, Kylie Jenner. Things may be changing.

DOUBLES from £89 B&B at the Kefalonia Grand hotel (kefaloniagrand.gr); doubles at Eliamos from £635 B&B (eliamos.com). Stansted-Kefalonia return flights from £109 (ryanair.com).