It goes without saying that Crater Lake itself is stunningly beautiful. That said there isn't much you can do here that can't be done in a full day or 2 at most (unless you want to hike in forest). There are some nice dayhikes that offer different views of the lake. I hiked to Discovery Point and back and then up Garfield Peak (though the top was technically closed for snowfields).
Away from the lake I also hiked Godfrey Glen and Annie Creek Canyon trails, which offered some cool scenery of pumice erosion, including smaller versions of The Pinnacles. Because the E and SE section of Rim Drive was still closed in mid-July, we couldn't hike Mt Scott or see the Pinnacles from the normal routes. I did see the latter on our way out by following 10 miles of gravel forest service roads to come in the back way. I had to hike the last 3 miles of road because it hadn't been cleared of downed trees yet. It was worth the hour hike and I also learned that this used to be the official entrance to the park decades ago!
For the very adventurous, Llao's Hallway is a pumice slot canyon just a few hundred yards north of 62 on the way in from the west. Don't go solo, take a rope, and you will get wet and dirty. Turn back if you hit blocks of snow in the slot as I did.
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