Upper Big Lost River
The Big Lost River, outside of Sun Valley, offers two amazing experiences ranging from true wilderness fly fishing on freestone tributaries in the high desert to fishing the cottonwood-forest tailwater section below Mackay Reservoir. You can read more about the Lower Big Lost River Here.
The upper Lost River holds a variety of trout living in the mountainous stretches of the watershed. It is not uncommon for guests to try for the “Lost River Slam” which includes catching one each of Rainbow Trout, West Slope Cutthroat Trout, Snake River Fine Spotted Cutthroat Trout, Brook Trout, Cutt-Bow, Grayling and Mountain Whitefish in a single day! That is seven species of wild fish in one river! The high-country nature of the upper Lost River drainage makes it very user friendly for all skill levels of fly angler, it also makes it a great place to relax, breathe fresh air and listen to nothing but the sound of wind, water and maybe the occasional laughter of a happy fisherman. Large flies are the norm, and fish from 8 to 20 inches are common. There are some wonderful hatches here, but it is also a great place to cast attractor patterns, big bushy dry flies, nymph boulder strewn runs and cast Streamers under overhanging tree limbs. Trust us, the views here are as good as the fishing!
USGS water flow and temperature gauge for Big Lost River: HERE
*Note: Due to the distance and dirt roads that keep the Lost River system quiet, we only offer ¾ day and full day trips to the upper Lost River area, and only full day trips to the Lower Big Lost River.