Popularly rated as one of the most spectacular hikes in America, this circuit is perfect for backpacking. A friend and I attempted to do this as a 2 day (1 night) backpacker, but due to inclement weather got pushed to a 2 night (slightly over 48 hr) finish. Thunderstorms at 12000+ ft are not to be trifled with. Picture perfect from start to finish, this loop features ever wildly changing scenery to keep even hikers with the shortest of attention spans interested.
As others have commented....this trail is rocky but totally worth it !! My GPS clocked in at 3.7 Miles and 614ft of altitude gain so YMMV. Bring water!! The trail is well marked and well traveled. If you get there before sunrise, you can drive your car to the trail head without much issue.
We did this trail in late October 2016, it was 16 miles out and back according to my phone. There is a moderate incline over a long span which makes the hike more bearable. The last 2 miles are very uphill but the view is worth it. We were the only ones in the hot spring on a Sunday afternoon which was lovely. We hiked back down in the same day and made it to the car before the sun went down.
Great trail...only difficult part was finding a parking spot (Oct 23?- shuttle not running). Rocky trail with altitude gain so plan accordingly...appropriate hiking shoes (yes, don't wear high heels, flip flops or Berkenstock clogs) and bring water. Lots of dogs on the trail, too.
Such an amazing place to visit - I arrived too late in the day to do the Crater Lake hike, which was a bummer. But I just enjoyed the view, walked around and took some pictures. If I had it to do over again, I would have gone very early in the morning (before the buses start running at 8am) because it does get crowded and the lighting is better for pictures in the morning. I can't wait to come back!