This was a hard, not moderate trail for myself and my husband (admittedly not the most in shape). The trail is nearly all elevation gain (2300 ft). The trail spilts halfway to the lakes with an option to go to Crystal peak or to the lakes high up in the crook of the mountains. A few places on the trail were flat or gently sloped but they were few and very far between. Then of course the way back down is tricky for ankles and knees, being all downhill. The lakes are beautiful, the scenery is spectacular, and I was happy to discover so many late in the season wildflowers and of course huckleberries! There is a toilet at Lower Crystal lake as well as a few marked campsites.
Take plenty of water! Both of us had emptied 32oz water bottles and didn't have any backups in our car. The journey home included stopping to refill on water.