Abisko

The season runs from early September to late March, and the strongest, darkest conditions are December to February. What makes this valley different is not the aurora — it is no more frequent here than anywhere else at this latitude — but the cloud. Abisko sits in the rain shadow of the Norwegian border peaks and is one of the driest places in Sweden, so the sky above it is open on nights when the coast and the country east of here are closed in. You are not buying better odds of an aurora. You are buying a better chance of seeing the one that happens.

March, if you only do this once. Both months sit inside the season and both give you a proper day as well as a night — about eleven and a half hours of light in March, thirteen in September. The difference is the ground and the weather. March is deep snow, settled skies and everything winter is for: sledding, skiing, the frozen lake. September is autumn colour and milder air, but it is the least settled stretch of the year here, and the rain shadow helps you less when the cloud sits low in the valley. September is the better second visit.

Three. One night is a coin toss anywhere on earth, including here — the aurora is a forecast, not a timetable. Two improves matters. Three, in this particular valley, means it would be genuinely unlucky to leave without seeing something. We build our winter journeys around that number for exactly this reason, and we would rather say so now than have you plan a single night and hope.

Two ways, and neither of them asks you to drive. Fly to Kiruna and we meet you at arrivals: Abisko is just under a hundred kilometres west on the E10, a little over an hour in summer and longer in winter, when the road is cleared but rarely quick. Or take the train, which is the better arrival — Abisko sits on the Iron Ore Line, the freight railway between Luleå and Narvik, and it stops twice in the valley. You want Abisko Turiststation for the national park, the chairlift and most of the lodging; Abisko Östra is the village stop, a little further on. Once you are here the valley is walkable, the trailheads are served, and the only thing a car would add is a reason to be on ice in the dark.

It is worth planning for, because it is commoner in the months you are most likely to be travelling. Kiruna is a small airport, almost everything routes through Stockholm Arlanda, and winter weather this far north diverts aircraft. Which is the argument for not booking the last connection of the day, and for leaving any slack in your plan at the Stockholm end rather than this one. If a flight moves, we move the rest of the chain with it — the transfer, the lodge, the table that now has to be later — and you make one call rather than four. What we cannot reschedule is the aurora, which is the other reason three nights is the number.

Mid-winter nights sit around minus ten to minus fifteen, and drop past minus twenty when the sky is clear — which is, inconveniently, exactly the night you want to be outside. The record is near minus thirty-five. Bring warm base layers, a hat that covers your ears and boots you can stand still in for an hour, because standing still is the activity. You do not need to buy an expedition parka: proper outer clothing and boots come with the lodges. The cold is a packing question, not a reason to reconsider.

Yes, and a trip built only around the sky is a trip that can be ruined by one cloudy week. The Kungsleden, Sweden's long-distance trail, starts here — you do not have to walk all of it, and a day on the first stretch with the Lapporten valley ahead of you is the point. There is the chairlift up onto open fell, the frozen length of Torneträsk, dog sledding and the national park itself. In summer this is a hiking destination that happens to have no darkness in it at all.

If the lights are why you are coming, stay in the valley. Kiruna has the airport, a town and the ice hotel half an hour the other side of it, and it is a perfectly good base for everything except the one thing Abisko is for — Kiruna sits outside the rain shadow and is measurably cloudier. Driving out here each evening on the chance of a clear sky, then driving back at one in the morning, spends the advantage you came for. Most of our winter journeys use both: the ice and the town from Kiruna, the sky from here.

The chairlift and the station at the top are busy, and in February they are busy with people who have all read the same article. The valley is not. It is a national park with one small village in it, and you can walk fifteen minutes from a warm room and be alone under the whole sky — no ticket, no guide, no minibus. The thing worth paying for here is someone who knows which night to go out and which side of the lake to stand on. It is not the entrance fee.