Here is an account of two hikes in the Rocky Mountain Front area - 20 miles west of Augusta in the Sun River Canyon. The trailhead is a 118-mile drive south of Browning. https://bigskywalker.com/2017/04/08/cas ... er-canyon/
There are unlimited opportunities for hiking along the Rocky Mountain Front and, of course, into the Bob Marshall Wilderness south of Glacier National Park. The distances can be quite staggering though. If you plan on venturing this far from Glacier I would suggest camping down that way or planning for a backpack into the Bob. IMHO it's not worth the time to Drive from Saint Mary or East Glacier to the Sun River Canyon and return in the same day. From Saint Mary it's about 125 miles one way from Saint Mary to Augusta then another 20-30 miles of mostly gravel roads to the Sun River Canyon.
"If you are not curious, you will learn nothing" -Goethe-
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