Also in common with the route to Refuge de Sales, the entire walk is within the Sixt-Passy National Nature Reserve, which covers some 9,000 ha ranging in elevation from 900 m up to more than 3,000m.
The diversity of the environment within the reserve means it supports a wide variety of fauna and flora and the slopes around Alfred Wills are a great place to spot marmots, particularly in the early evening.
Alfred Wills makes a great overnight stay for families with younger children - it's far enough to be challenging, but not too tough, and the location and sleeping arrangements in mixed rooms with complete strangers make for a great adventure with the option to return a different way in the morning.
Dinner is usually soup, a choice of main course (fondue or meat), cheese and dessert although on one visit we were treated to a wonderful Nepalese curry and a presentation about the work of the local charity Play for Nepal.
To get to the start of the walk, turn right over the bridge in Sixt, following the signs for the Cascade du Rouget and carry on up past the waterfall until the road ends at Le Lignon. Park here, or as close as you can get, as it gets very busy in Summer and at weekends.
The route climbs steadily through the woods for the first half hour or so towards the waterfalls of Sauffaz and Pleureuse.
At the signpost where the route to the Refuge de Sales splits off, turn left for the GR5 and Refuge d'Anterne. After a steady climb up of around 600 m, you'll reach the Collet d'Anterne, with amazing views of Mont Blanc; it's just a shame there's a giant red and white pylon there too. It's then a lovely meander of around 1.6 km across a wide, generally flat, marshy plain, crossing the Ruisseau (stream) d'Anterne to the refuge itself (1,807 m).
En route, you'll pass an enormous rock with trees growing on the top of it which always makes me think of a Japanese Garden for some reason (albeit one of Brobdingnagian proportions!).
From the refuge, assuming you're not continuing to Lac d'Anterne or Col d'Anterne, you can either retrace your steps or continue a little further up to the Petit Col d'Anterne (2,038 m) before heading down into the Cirque des Fonts where you'll find the Refuge des Fonts (1,360 m), which makes a great stop for a drink or lunch.
It's then a relatively short distance back down to near the start of the walk - note that if you parked up at / close to Le Lignon itself then the route via the Cirque des Fonts brings you out lower down. We have experienced the odd mutiny at that point and so a volunteer might be needed to go and collect the car.