Overview Lake Isabelle is a 4 mile out and back trail located near Nederland, Colorado that features a great forest setting and is good for all skill levels. The trail is primarily used for hiking and is accessible from July until October. Reviews Photos Tracks Michael Cox (456) 8 months ago N/A: 9 Completed 8 Reviews Nice trail. Tons of mosquitoes. The lake was quite low. Valerie Doubleday (272) over 1 year ago N/A: 7 Completed 7 Reviews Absolutely breathtaking hike. For the most part it's fairly easy. Multiple gorgeous places to take pictures or stop for a picnic. I recommend going in late June or early July to see both the wildflowers and the waterfall. If you decide to pass the lake and continue on to Pawnee Pass be aware that it does get more difficult. This trail can be crowded so go during the week if possible. Worth paying the fee at Brainard Lake entrance. One of the most beautiful places ever.