Relatively straightforward, with a total round trip mileage of 13 miles, or a bit more. From "The Loop" (where there is parking) take the very good, well-marked trail to the Granite Park Chalet, a distance of four miles. Approximately a hundred yards or so from the Chalet, the trail you're on joins the Highline Trail, at which point follow the Highline Trail a short distance—maybe a quarter mile—as though you were going south, to Logan Pass. Soon, you'll come upon the trail heading off left, leading up to an unnamed saddle (see picture). Upon reaching this saddle (stop and marvel at the view!) the human trail ends, you are passed over to a goat trail, and it becomes distinctly more fun—or at least more interesting!

From the saddle work your way back to the left, losing elevation slightly, until reaching the point where Mount Grinnell first comes into view, and from then on it's basically just a matter of pointing to the summit, although you will want (actually, you won't have a choice, you'll HAVE) to work your way over so as to keep left of the summit ridge.

On the return we chose not to retrace our steps, but to cross the Swiftcurrent Glacier, which is in the basin immediately west of the mountain. Crampons were not needed (July 18th), but would probably be advised earlier in the summer, or definitely recommended if the surface is frozen; this is by no means a difficult or treacherous glacier crossing, and it is not necessary to rope together; however, the slope is just steep enough you will want to have an ice axe. Crossing the glacier helps to avoid the huge elevation loss encountered by crossing the bottom of the basin below the ice.

Upon reaching the far (west) side of the glacier, it is a simple matter of climbing out of the basin, where, from the top of the ridge, it is easy to bushwhack down the slope to once again join the Highline Trail, at which point the trek then becomes just a routine matter of walking back to the parking lot.

Essential Gear

If crossing the Swiftcurrent Glacier on your descent (which is recommended, as doing so will save a great deal of elevation loss), an ice axe is needed; if the surface is frozen crampons would also be required. Ropes are not necessary.