THE ICEHOTEL IN NUMBERS

Number of weeks it takes to build Ice blocks used in its construction Cubic metres (1,059,440 cubic ft) of snow and ice mix in walls, floors and ceilings you could fill when hotel melts Years since the first Icehotel was built Distance in miles that the Icehotel lies north of the Arctic Circle Duration in hours of direct flights from Heathrow to Kiruna if we could track them down.

We drive for 20 minutes, away from the modest light pollution of Jukkasjarvi, to a secret spot that Pontus knows – a vast, frozen lake with a shallow northern horizon. Here we sit on the lake’s thick ice under a star-filled sky and, to my disbelief, within minutes a subtle white arch emerges. The display teases us, softly pulsating and retracting, before a giant celestial doorway opens, dragging the emerald aurora apart like iron filings to a pair of magnetic curtains.

Having grown up in northern Sweden, Pontus has seen the northern lights thousands of times before, but suddenly he pipes up, excited by something he has seen.

“You see that dark patch?” he says, pointing at pockets of dark space within the hazy green sky. “I’ve heard people speak of the ‘black aurora’ before. It’s super rare, but I think that could be it.”

The revelation that we might be witnessing a mysterious quirk in the northern lights puts my Philip

Pullman fantasies into overdrive. We are, I decide, almost certainly gazing into a parallel universe.

Over the next hour, the aurora slowly sinks into the abyss until we are left with nothing but numb toes and memories. In a way, I’m thankful that the show came to an end. Like the Icehotel, meticulously crafted before melting away, it is perhaps the ephemeral nature of the northern lights that makes it so magical.

Three nights’ B&B costs from £1,073pp, based on two sharing, through Discover the World (discover-the-world.com). The price includes two nights in a warm room and one in an ice room, return flights and transfer. Excursions: husky sledding (from £122), snowmobiling (£168), ice sculpting (£65), northern lights safari (£168) and winter survival skills (£107). Chef’s Table starts at £186.

To watch the full video of Greg’s experiences at the Icehotel, see: telegraph.co.uk/tt-icevideo