I have found several sources that state the South Spur Route is about 5.7 miles as mentioned in this description. However, I believe this climb is further than that. The trail to the lunch counter where we camped was 5.1 miles according to my GPS. From the lunch counter it was 2.4 miles to the summit (we did do a bit of switch-backing on the snow fields above the lunch counter). Someone preparing to make this hike should plan on 7.5 miles.