Alta Badia or Crans-Montana: the bigger valley or the higher plateau?

Size: Alta Badia has more at the door and far more in reach

Start with the areas as they are usually counted. Alta Badia's own sector is 130 kilometres. Crans-Montana's is 140, all of it linked, and three independent sources agree on that figure to the kilometre. On that count Crans-Montana is the bigger of the two, by 10 kilometres.

Our own measure of the graded piste around each village is a tighter count, and it turns the order round. We make it 124.5 kilometres at Alta Badia and 85 at Crans-Montana, a gap of about 39 kilometres.

Then there is what lies beyond. Alta Badia sits on the Sella Ronda, the circuit of lifts and piste around the Sella massif, and from a base on it around 500 kilometres is reachable by lift without a bus. Dolomiti Superski does not publish that number. It is our own sum of measured kilometres across the linked areas, so take it as approximate. The 1,200 kilometres printed on the pass is something else again: twelve areas, and only four of them are joined by lift.

If your group judges a week by the distance covered, that settles it: from Alta Badia, the confident skiers can go a long way before they repeat a run.

Altitude: level at the door, Crans-Montana higher on the hill

The villages are close: 1,568 metres at Alta Badia, 1,500 at Crans-Montana. The gap opens up above them. Crans-Montana's skiing reaches 2,868 metres by our measure, 359 metres higher than Alta Badia's 2,509. More of its piste sits high, too: 51 percent is above 2,000 metres, against 22 percent at Alta Badia.

Both pass our snow sure test, which asks for more than half the piste at or above 1,800 metres and skiing that reaches 2,500. At Crans-Montana, 79 percent of the piste we measure is above 1,800 metres, up to 2,868 metres, the fourth biggest share of the 15 Swiss resorts we cover. At Alta Badia it is 65 percent, up to 2,509 metres, a top that clears the bar by 9 metres.

Nobody can promise snow. But if a thin January is what worries you most, Crans-Montana has more of its skiing comfortably clear of the line.

The skiing: Alta Badia is blue, Crans-Montana is red

Here the two part company. Alta Badia has 76 kilometres of blue and easier piste, 61 percent of what we measure and the most of the 10 Italian resorts we cover. Forty percent of its piste is gentler than 15 percent, the joint fourth biggest share of the 55 resorts we cover, and only 15 percent is steeper than one in four, against 26 at a typical resort we cover.

Who each one actually suits

Alta Badia suits families, food lovers, couples and groups of mixed ability. The less confident get more easy piste than at any Italian resort we cover, and the strong skiers can set off round the Sella Ronda for the day and meet the others for lunch. Lunch is a serious business here, with Ladin cooking in the mountain huts and a gourmet ski safari that moves between restaurants.

Pick the village with care. Corvara is the largest, with the most bars; Colfosco is quieter and handy for the Sella Ronda; La Villa is small and suits families; San Cassiano is the polished one, known for fine dining. Evenings everywhere are calm.

Crans-Montana is sunny and smart, and it suits families and people who choose a resort for the sunshine. It is also one for anyone who wants golf and spa to be part of the week. On the measured terrain, it suits intermediates who are comfortable on red and want the higher snow, and a stronger skier who wants more black than Alta Badia can give.

The bit nobody tells you

Crans-Montana's colours make it look harder than it measures. Its reds average a gradient of 19.2 percent, and only five of the 55 resorts we cover have gentler reds on average. That is under the Swiss average for a red, 19.9, and well under Alta Badia's 21.7. Its blues average 13.3 percent against Alta Badia's 14.4. And 36 percent of its piste is gentler than 15 percent, not far behind Alta Badia's 40.

These are averages per run segment, and a run's grade is set by its steepest pitch, so read them as how the week feels rather than a promise about any one run. Grade colours are not comparable across countries either, which is why we lean on the measurements. The upshot: an improver who is ready to start on red will find Crans-Montana's reds among the gentlest we measure, and there are 50 kilometres of them. The 22 kilometres of blue is not the whole of their week.

The reverse is true at Alta Badia. Its reputation rests on how much blue it has, but its reds average steeper than the Italian average of 20.4. A confident intermediate will not find them soft.