There is a small parking area next to a small cemetery on Rocky Springs Road to park at.
Take the Crystal Larsen TH Road through some forest for maybe a quarter of a mile before reaching a split. Continue west/south - not north, which is the Larsen Lakes Trail #236. The road here passes through aspen and can be steep/muddy at times. It soon will turn into a singletrack that is very clear to follow. The trail leaves the aspens to enter a large meadow with some views, but you're still a bit low elevation.
The trail will head into a very dense aspen forest which may have debris on the trail after a storm. The forest will abruptly turn to pines before opening up to a large boulder field. The trail skirts around the field so it is easy going here. There should be some good views to the south as well. At just under 11,000 feet in the boulder field, you'll pass Hay Lake which makes a good resting spot.
You'll pass through another spot of pine forest and another boulder field. After this field, there is a somewhat steep spot, but no scrambling is required. The trail then levels out along what might have been a very old forest road. The trail splits - you can stay on the wider road-like section or take the trail slightly higher up on the ridge. They will come back together in a short distance. Just after this, the forest begins to open up into a very large and flat meadow. Here you can take the Crystal Lake Spur
to see the trail's namesake lake.
After Crystal Lake, the trail will remain relatively flat and pass through wide open meadows. There are a few forested areas, but much of the next seven miles is wide open - keep an eye out for elk and other animals! You'll never be too far from a grove if the weather takes a turn for the worst and you want to hunker down, but you'll be over 11,500 ft. the rest of the run so also be mindful of the sun.
You'll cross Larsen Creek at about 6.6 miles in and the Larsen Lakes Trail #236. Here the trail enters the Uncompahgre Big Blue Wilderness, and the next two miles are completely open.
At about the eighth mile of the trail, you'll cross Elk Creek. You'll more or less follow Elk Creek for the next 1.75 miles before the trail heads north away from the creek. Eventually, it will meet the Ridge Stock Driveway #233
where the trail ends.