Backpack Trail Guide

Trails / Montana / Glacier National Park

Highline Trail to Fifty Mountain

Glacier National Park (Logan Pass to The Loop via Granite Park, Fifty Mountain, and Flattop)

The Highline Trail leaves Logan Pass and traces the Garden Wall along the Continental Divide, one of Glacier National Park’s best-known day hikes. Past Granite Park Chalet it becomes a backpacking route: Glacier Guides calls the section north to Fifty Mountain “the lesser seen section of the Highline Trail” and a permit there “extremely coveted,” partly because the trail is part of the Continental Divide Trail.

10Adventures lays out a four-day version that returns to Going-to-the-Sun Road at The Loop by way of Flattop Mountain.

The hike

From Logan Pass, Hiking in Glacier describes about 0.3 mile of ledge, 6 to 8 feet wide with a hand cable, above drops of 100 feet or more. Haystack Pass comes at about 3.6 miles, and a steep side trail climbs to the Garden Wall at 6.9. 10Adventures puts the first night at Granite Park, 7.8 miles from Logan Pass; Hiking in Glacier says the campground is on a spur a little over half a mile below the chalet. Glacier Guides adds that Granite Park Chalet can book up to a year ahead, has no running water, and sells snacks.

Day two, 11.3 miles to Fifty Mountain, is the long one. About 3 miles past Granite Park is Ahern Drift, a steep snow patch below Ahern Pass. 10Adventures calls it “dangerous and exposed” and says rangers advise crossing only with the right gear; Backpackers Review says that by August the drift is usually small enough to walk around or across. 10Adventures’ North Circle guide names Cattle Queen Creek, about 9.5 kilometers out of Fifty Mountain, as a lunch and water stop on this leg.

From Fifty Mountain, 10Adventures continues 6.1 miles to Flattop campground, crossing an old burn with little shade, then descends 5.6 miles past the Packers Roost junction to The Loop. Hiking in Glacier says the 2003 Trapper Creek Fire left many dead trees along the lower trail.

Weather shapes this trip. Glacier Guides notes that most of the trail is at or above treeline and conditions change fast. A Gossamer Gear trip report from late September 2013 describes two to three inches of overnight snow at Fifty Mountain, a grizzly in a high meadow nearby, and a retreat down the Flattop trail to Packers Roost because snow covered the Highline.

Outside, in 2008, described a 30.5-mile alternative that continues north from Fifty Mountain to Waterton Lake. For a full loop that links Fifty Mountain with the Belly River country, see the North Circle Loop, and for a shorter crossing of the Divide, see Gunsight Pass.

Tips

Camping

Glacier requires a wilderness use permit for all overnight camping, and you may camp only at the campground and on the date on your permit. Advance reservations, through spring lotteries and a general on-sale on Recreation.gov, cover about 70% of sites for trips between June 15 and September 30; the NPS sets aside about 30% of sites parkwide for walk-up permits, available in person no more than one day before your trip. Each permit allows up to four people per campsite.

The campgrounds on this route are Granite Park, Fifty Mountain, and Flattop. Hang food, garbage, and scented items from the food poles or use the bear boxes, with your own bags and at least 25 feet of rope. Recreation.gov says wood fires are permitted only at a few select campgrounds; the NPS’s 2008 guide listed both Granite Park and Fifty Mountain as no-wood-fire camps. 10Adventures notes a pit toilet at Fifty Mountain.

Inside Intel: Backpackers Review recommends the side trip from Fifty Mountain to the Sue Lake overlook, about 2.7 miles and 1,000 feet round trip, and reminds hikers to store their food before heading out.

Trail facts

The Lowdown

Crossing Ahern Drift on the Highline:

About 3 miles past Granite Park, steep Ahern Drift sits below Ahern Pass, and the trip ends with a 5.6-mile descent from Flattop to The Loop. See how to use poles on snow and long downhills alike.

Read the pole tips →

Where this comes from

This page draws on the sources below, along with other guides and trip reports. Links go to the original pages.

Before you go: This page is based on published trail guides, trip reports, and reviews, along with official park and agency information where we could find it. It’s meant to help backpackers discover new trails, not to replace current, official information. Conditions, closures, permits, campsites, and water sources change, and some details here may be out of date or wrong. Confirm everything with the managing agency and check current conditions before you head out, and don’t rely on this page alone for safety or navigation. Backcountry travel involves risk.