TREE-TOPPED limestone islands rise out of the emerald waters, appearing through the eerie, lingering mist like something from the set of Jurassic Park.

There is a collective dropping of jaws as the first of Halong Bay’s 1,969 tiny bodies of land drift into view, the wide-eyed “wows” the only thing breaking the monotonous, but somewhat soothing, whir of our boat’s motor.

Just 30 minutes earlier we were being welcomed on board one of Paradise Cruise’s spectacular fleet, the Paradise Luxury.

Greeted by a waterfall of lotus flower petals fluttering down into our path as we stepped on to the wooden deck and having been introduced to our personal butler, we quickly realised this wasn’t your average sightseeing trip.

A bedroom bigger than our apartment, kitted out with our own deck to enjoy breakfast on if we wished and a jacuzzi bath, situated next to a gym and a spa with treatments available on request – our only problem was how we were going to soak this all up in just 24 hours?

Halong Bay is a three-hour drive from Hanoi and simply a must-do if you are visiting north Vietnam, but we were treated to a luxury transfer and then a beautiful buffet to feast at one of Paradise’s partner hotels before boarding.

We worked it off on our first excursion, kayaking around Luon Cave – the less adventurous can take a boat. Heading through a hollowed-out limestone arch, we rounded the bay beyond in an ultimately unsuccessful search for monkeys, enjoying the sunshine and stunning views all the same.

Having picked our way through a sumptuous seafood buffet for lunch, it was time for our afternoon activity – a tour around Sung Sot Cave, or ‘Surprise Cave’ as our knowledgeable guide Evan named it.

Spoiler alert, but the surprise was the discovery of three caves within the original formation, and a snigger-inducing phallic-shaped rock for good measure.

The prize for pacing up, down and around the many steps of Sung Sot was a breathtaking view back across the bay, its forest-flanked islets interspersed by sightseeing ships steaming from one eye-popping destination to another.

Back on board the Paradise Luxury, we took part in a cooking class, rustling up some spring rolls and scoffing them twice as quick before it was time to get dressed for dinner.

Now, we’d been told to dress like ‘Kings and Queens’ for the banquet, little did we know this would involve donning traditional Vietnamese royal gowns. It was great fun, and complemented by wonderful food, with the evening topped off by some late-night squid fishing.

Having risen early to participate in tai chi on the top deck the following day, we headed out for a morning excursion to Titop Island, a 200-step climb to yet more Instagram-wowing views over.

Our final pit stop was breakfast back on the top deck, watching the islands whiz past as we headed for port, speculating whether we would ever see anything quite like it ever again. A truly mesmerising 24 hours.