One of the best options if you have to settle for a campground close to the road or are coming into camp late in the day (weekdays only). Lilly Lake campground would be my third pick for best roadside campgrounds along Mirror Lake Hwy. The campsites at the far west side of the campground are far enough away from the road to offer some seclusion, but the sites themselves are pretty closely spaced.

The best thing about staying at this campground is easy <5 min access to 3 great lakes for fishing! There is the namesake lake whose entire west side is covered in beautiful lillypads. A tiny bit south on the Hwy is the uniquely shaped Teapot Lake and directly across the road from Lilly Lake is Lost Lake, which also hosts the Lost Creek Campground is case Lilly CG is full. Camping here is steeply priced like most other spots along the Hwy but it stays open a good bit later into the fall season than most of the other CG's. There are 14 single sites that cost $23 a night. In addition to the camping fee you'll also need a Mirror Lake Hwy Recreation Pass which is $6 for 3 days and $12 for the week. If you have an America the Beautiful Interagency Pass then that will cover the recreation fee but not the camping fee.