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Birthday Chutes


A classic backcountry playground above the Observatory in Alta Lakes Basin

Ski Touring Severe

718 m
0 m
318 m
0-1 hrs
Low Point
3.4 km
High Point
3.7 km
Birthday Chutes Map

The north-east facing Birthday Chutes of Alta Lakes Basin are a cherished backcountry location in the San Juan Mountains. Named by a crew celebrating their birthdays picnicking in the Basin or renting out the Observatory for overnight parties, this area is the perfect gift of sweet turns, good aspect and nice pitch. The main entry point to Alta Lakes is via a single backcountry access gate at the base of Bald Mountain on the Telluride Ski Area side. Another option is up the Alta Lakes Road from the classic Colorado ghost town of Ophir. Touring skins, split board or snowshoes are necessary ( a snowmobile is optional) along with all your backcountry safety gear - beacon, probe, shovel, first aid, food, water and expert awareness. It's best to allow a full day or book a bucket-list stay at the Observatory with a bunch of good friends.


The Ski Area gate leads into a mellow saddle entering the North West side of Alta Lakes Basin. As it starts falling away cruise left through a fun forest until the basin opens up in front of you. The immediate view now is Silver Mountain standing proud behind Palmyra. An extreme couloir named 'The Wire' falls off its peak. To the right of that is Silver Chute and then half way down the ridge line the Birthday Chutes invite you across an amphitheater of Rocky Mountain beauty. Make your way across the Basin for some of the finest high alpine snow on Earth. Navigate around the Lakes toward an old mining structure known as the Trestle Shot then go straight up the edge of the Chutes.

Advanced understand of snow science is an important tool in your skill set. There are times when this is a no-go-zone and you'll turn around. The attractive sunny side has far smaller windows of opportunity - south faces are more unstable with hidden shallow rocky sections due to greater exposure to wind effect and avalanches. While the northern faces, especially the Birthday Chutes, and aspects that remain out of sun's reach most of the day can preserve that magical Colorado champagne for weeks on end. All precautions regarding snow pack and current conditions are vital to enjoy this area. When it's on it's as good as it gets. The best line is to pitch left and take longer runs down through Birthday Cake toward the Ophir entrance. Exit out the way you came or along the snowshoe trail south of Bald Mountain onto Galloping Goose.



Steep skiing at 38-45 degrees. This requires very good technique and the risk of falling has serious consequences.

Medium Exposure (E2)

2 out of 4

As well as the slope itself, there are some obstacles (such as rock outcrops) which could aggravate injury.


4 out of 4

In the high mountains or remote conditions, all individuals must be completely autonomous in every situation.

Best time to visit

between December and April


  • Cliffs
  • Walk Required

Equipment required

  • Skins