The eastern portion of the famed Going-to-the-Sun Road is where you really get to see what glaciers are capable of. Their awesome icy power is now mostly a thing of the past in this park named for them. Remnants of much larger glaciers can be viewed from Going-to-the-Sun Road, at Jackson Glacier Overlook, and Sperry Glacier from Hidden Lake Overlook, 1.5 miles up a trail from Logan Visitor Center.
Glaciers are basically rivers of ice that are born when there is more snowfall every winter than melts every summer, compacting into ice. A hard brittle surface layer overlies a more flexible underlayer of ice, which due to the immense pressure above it, the angle of the mountainside, and gravity, begins to move, becoming a glacier. Glacier Park’s glaciers, though ancient by human standards, are all geologically young, born in the Little Ice Age. This period of cooling and glacial advancement, mostly in the Northern Hemisphere, began somewhere between 1250 and 1450, and ended in the mid-1800s. Since then, glaciers worldwide have been receding. In 1968, the USGS listed 34 glaciers in Glacier Park; currently there are 27.
How do glaciers carve and sculpt the landscape? These rivers of ice are filled with rocks and gravel that grind and scour like sandpaper, creating broad U-shaped valleys, sharp peaks, and cirque lakes. The piles of rocks and debris on the sides and in front of glaciers are called moraines. Horns are pointy peaks, and arêtes long narrow ridges, both formed by glacial flow. Hanging valleys were formed by glacial tributaries moving down side-canyons, and often contain waterfalls.
Contributing to the spectacular nature of Glacier Park’s scenery is the Lewis Overthrust, a much older geological feature caused by the collision of two tectonic plates 170 million years ago, giving birth to the Lewis and Livingston Ranges of the Rocky Mountains, in Canada and Montana. The upper Precambrian rocks on this long eastward-moving thrust fault are 1300 million years old, covering younger softer Cretaceous rocks underneath.
Clouds formed a uniform, hazy and somewhat drab overcast on the morning we took off from St. Mary Campground to drive the eastern portion of the Going-to-the-Sun Road, not an optimal day for viewing or photography, but our last day at Glacier. There are numerous pullouts to park and view the surroundings, and we took our time doing so.
Oft-photographed Wild Goose Island at the western end of Lake St. Mary is a tiny picturesque islet growing a few spruce and fir trees, presumably a landing or nesting place for wild geese. The islet sits pretty with a dramatic backdrop of glacial peak after peak.
Sunrift Gorge pullout is a must-stop for some very easy walks to a narrow gorge and waterfalls. The trail north of the bridge takes you on a 200-foot walk (40 foot climb) up to narrow Sunrift Gorge, through which Baring creek rushes. South of the bridge, walk past the grizzly-bear warning/fire hazard signs 1/3 mile down (100 feet) to 40-foot Baring Falls. A bit further up the road, at the St. Mary Falls trailhead, you can hike to two more waterfalls, St. Mary Falls, 0.8 miles and 260 feet down, and Virginia Falls, another 0.7 miles and 285 feet up.
Jackson Glacier overlook provides impressive views of one of Glacier Parks remaining 27 glaciers. A young couple next to me were delighted to learn from the interpretive sign that the "ice began its retreat in 1860." "See, this proves it: global warming is bunk; SUV’s have nothing to do with it. It was already happening before there were cars!" I bite my tongue, guardedly roll my eyes, and think better of saying anything.
Past wide-open glacial vistas, over bridges built of park rocks, under the late-summer trickle of Cataract Creek which passes under the road, and passing through a tunnel, we make our way up to Logan Pass. Roadwork is in progress. We’re pleased to see they’re using portable solar cells to operate a temporary stoplight.
Logan Pass Visitor Center has natural history displays, good selections of books and posters, and rangers to answer questions. But I’m eager to begin my hike to Hidden Lake Overlook, 1.5 miles up from the visitor center, also covered in this journal. Bob stays at the center looking through books.
On the way back down from Logan Pass in gathering dusk, we pull over once again to get some more shots of an irresistible vista, when I hear rustling to my left, on the mountain-side of the road. It’s a couple of bighorn sheep, crossing a stream. Soon they look up attentively from where they came, more rustling. Four more bighorns! I watch, enthralled, taking photos and hoping there’s still enough light. Bob, across the street, hasn’t noticed them and I keep quiet, not wanting to scare them. They run off anyway all too soon, but it’s a nice end to our day on Going-to-the-Sun Road.
That night it snows, enough for Logan Pass to close temporarily the following day, and we leave Glacier Park. For up-to-date information on all park roads status, check Glacier National Park’s What’s New section.
For a unique view of Going-to-the-Sun Road and Glacier Park, consider taking Blackfeet Indian run and operated SunTours, also known as the Blackfeet Cultural Tour. On these daily tours that run all summer, Blackfeet Indian guides show visitors historical, natural and cultural features of their Glacier Park homeland, on an all-day round-trip bus tour, east to west to east, with frequent stops and a lunch break at Lake McDonald.