The hike to Big Willis Lake is challenging at times, but the constant presence of the rushing creek and the gorgeous views of the lake more than compensate for the tough sections. To reach the trailhead, take Highway 82 from Twin Lakes for about 2 miles. The trail marker will be on the right hand side, and parking is to your left. To start this adventure, make sure you have rain gear, food, and water because this is a long hike, roughly seven hours round trip. While the trailhead may appear busy because there are other hikes nearby, the route to Big Willis Lake is lightly traveled. The weather changes very rapidly, so keep an eye on the sky and check the weather reports before heading up. The trail is a steady and very rocky climb, and it gains 2,400 feet along the way. This is not a good trail for a beginner or for small children.
As you start the adventure you will encounter multiple creek crossings, some with bridges and some without. This is a very dense wooded trail until you are exposed on the top. The trail follows a fantastic stream most the way. Make sure to check out all the vivid moss growing around the stream. The trail stays relatively well defined until you reach the big scree field that you will cross. Watch your step because some of the boulders are loose. You will come to an open meadow, which would be a great place to camp for the night. As you ascend to Big Willis Lake there will be a lower lake that is also beautiful. You will need to proceed through very overgrown shrubs... keep following the trail, and Big Willis will appear with it's green blue lake. This would be the perfect spot for you to have a lunch and enjoy the solitude with grand views or do a little fishing. The hike is difficult but well worth the reward. Leashed dogs are allowed on trail.