Here the road stops following the valley and starts climbing the wall of it. The Loop is a single tight hairpin, a looping bend where the highway turns back on itself to gain height on the west face of the Garden Wall. It is the first of the dramatic engineering features of the route, and after the gentle lake shore, it sets the tone for what follows: the road is cut into the cliff, with a stone wall on the outside and a deep drop beyond.
The engineers who designed it, working in the 1920s, faced an unusual constraint. The park service insisted that the road should fit into the landscape and not scar it, so the builders used local stone for the parapets and arranged the alignment to follow the contours of the mountain. Hand labour and dynamite carved the ledge, and the work was dangerous. The result is a road that looks as though it grew out of the rock, and it has become a National Historic Landmark.
For a motorcyclist, the Loop is a good test of your low-speed control. The hairpin is tight, the surface can be damp or gritty, and traffic from both directions may be slow and uncertain, with drivers looking up at the view and not at the road. Take it gently, stay well within your lane, and keep your eyes up through the turn. There is no guardrail to speak of, only the low stone wall, so a mistake would matter.
Beyond the Loop, the road climbs steadily along the face of the Garden Wall, a long, jagged ridge of the Continental Divide, with waterfalls dropping from the snowfields above. In early summer you can hear them over the engine, and in places the spray crosses the road. A few pullouts offer views back down the valley to Lake McDonald, a long ribbon of blue at the bottom of the trees.
Be prepared for the weather. The west side of the divide is wetter than the east, and clouds can come in quickly, dropping the temperature and the visibility. Wear a warm layer, even in July. There are no services here, so make sure you have fuel and water. And if the pullouts are full, as they often are by late morning, just keep going: the best views are the ones you catch in motion.