Big Lost River Retreat

Big Lost River Retreat is located in the Lost River Valley approximately three miles south of the small town of Mackay (pronounced “Mackie” with the accent on the first syllable) and 65 miles northeast of the resort community of Ketchum/Sun Valley. Access from Sun Valley is a 75-minute drive, more or less, via Trail Creek Pass and US Highway 93 from approximately May through November. As mountain snowfall begins to accumulate late in the year, Trail Creek Pass closes until spring, and access to the property shifts south to U.S. Highway 20/26, with drive times increasing to about two hours.  

Friedman Memorial Airport (SUN) in Hailey, 15 miles south of Ketchum/Sun Valley, is the nearest commercial airport and offers regular air service on Delta, United, and Horizon Airlines. Idaho Falls, approximately 90 miles southeast of the property, provides alternate commercial air service from Idaho Falls Regional Airport (IDA) on Delta, United, American, Horizon, and Allegiant. Mackay is home to a 4,400-foot by 60-foot asphalt runway capable of accommodating larger twin-engine aircraft, while the community of Arco, 25 miles south of the property, offers a 6,600-foot lighted runway that can accommodate most jet aircraft.

The Lost River Valley is considered one of Idaho’s most scenic areas and is among the state’s top regions for outdoor recreation. Spanning over 70 miles, the massive Lost River Range flanks the east side of the valley and claims seven of Idaho’s ten peaks over 12,000 feet, including Mt. Borah, the state’s highest peak at 12,662 feet. Two other formidable mountain ranges, the Pioneers and White Knobs, extend westward from the valley all the way to Ketchum/Sun Valley, offering incredible vistas and miles of roadless backcountry to explore. The Big Lost River originates from high mountain tributaries and meanders east and then south, providing irrigation water for farms and ranches around Mackay as well as outstanding trout fishing opportunities along its length.  

Mackay, with a population of approximately 500 residents, lies at the heart of the Lost River Valley and serves as the local service and social center. All general amenities can be found in Mackay, including groceries, fuel, banks, restaurants, and ranch and hardware supplies. While Mackay is primarily an agricultural community today, its roots go back to the mining days of the early 20th century. John V. Mackay, who discovered the famous Comstock Lode near Virginia City, Nevada, founded the town in 1901 as the site of a copper smelter and supply point for nearby mining operations. By 1919, Mackay-area mines were producing record amounts of copper, and the town was often referred to as Copper City. With an active railhead during the mining heyday, Mackay also became the center for the valley’s growing agricultural industry and, at one point, was the leading shipper of livestock in the state.

Sun Valley, Ketchum, and the other Wood River Valley communities of Hailey and Bellevue are an easy drive from Mackay and offer a host of summer and winter activities, including golf, hiking, fly fishing, cycling, and world-class downhill and Nordic skiing. One also finds numerous gourmet restaurants, art galleries, shopping opportunities, and cultural events to enjoy.

The elevation of the property is approximately 5,850 feet above sea level. The local climate is best described as semi-arid, with over 300 sunny days a year and annual precipitation of approximately ten inches. Summers are warm, with temperatures occasionally reaching the low 90s and cooling to the 40s at night. Winters can be cold, although the series of mountains to the west often create a moisture barrier, resulting in relatively open winters with little snowpack on the valley floor.

The centerpiece of Big Lost River Retreat is its 2,460± square-foot log home expertly crafted by Rocky Mountain Log Homes and White River Contractors from Hamilton, Montana, in 2016. Designed for a seamless blend of indoor and outdoor living, this thoughtfully designed residence features three bedrooms and three-and-a-half bathrooms, structured as two separate living suites (or “cabins”) connected by a spacious common area with a wood-burning fireplace that converts to a screened porch in warmer months. A covered porch, complete with an outdoor shower and barbeque area, wraps around three-quarters of the home’s exterior, providing approximately 2,000 square feet of outdoor living space and uninterrupted views of the picturesque Lost River Range and White Knob Mountains.  

The primary suite, referred to as Cottonwood Cabin, serves as the owner’s unit and includes an open living/dining area, a full kitchen with custom cabinets, a master bedroom, a master bathroom with a walk-in shower, a powder room, and a stacked washer/dryer. The living area also features a wood-burning fireplace that shares a chimney with the fireplace on the screened porch. Opposite Cottonwood Cabin, Trapper Cabin serves as the guest suite and includes two bedrooms with en suite bathrooms (one featuring a bathtub and the other with a walk-in shower), a comfortable living area, and a kitchenette fitted with a refrigerator, sink, and microwave. Throughout the home, wooden floors add to the rustic charm and lodge-like ambiance. The residence is complete with landline phone service, high speed internet access, and a complete security system.

The residence is surrounded by mature landscaping and well-maintained lawns irrigated by an in-ground sprinkler system. A gravel driveway leads to the south side of the home and offers ample parking space for vehicles, boats, RVs, and ATVs. The expansive area around the residence offers opportunities to develop an additional dwelling as well as practical enhancements such as a barn, workshop, or storage building. Additionally, the residence is served by a domestic well and septic system.

Annual Custer County property taxes are approximately $3,675, while annual McCaleb Estate homeowner dues are approximately $400. 

Rivaling its better-known neighbor to the west, Sun Valley, the Lost River Valley offers a low-key lifestyle, stunning scenery, high-quality federal lands, and an almost endless variety of recreation opportunities. Fishing, big game hunting, camping, boating, hiking, cycling, backcountry skiing, and ATV and snowmobile riding are only a few of the outdoor activities that are easily accessible from Big Lost River Retreat.

Trout fishing is among the most highly pursued activities in the area. Just a quick walk from the property via a private access easement is the Big Lost River, a mid-sized freestone stream that originates high in the Pioneer and Boulder Mountains and flows the length of the valley filling Mackay Reservoir and ultimately disappearing into the Snake River Plain east of Arco. Long known to locals for its outstanding fishing, the “Lost” is a destination for anglers from across the region and is frequented regularly by Sun Valley fishing guides and outfitters. Much of the upper river parallels Trail Creek Road, linking Mackay with Ketchum/Sun Valley, and is easily accessible to anglers via the BLM and national forest lands.

The lower river below Mackay Reservoir is renowned as a quality tailwater fishery with a reputation for producing large rainbow trout. Located approximately two-and-a-half miles downstream from the nearest public access point, Big Lost River Retreat enjoys private access to one of the most lightly used and productive reaches of the lower river. This section is highlighted by riffles, deep pools, and sharp meanders that hold hard-fighting wild rainbows that exceed 20 inches. In addition to stream fishing on the Big Lost, the area offers over 100 mountain lakes, many of which provide excellent trout fishing. Most of these lakes are found at elevations between 9,000 and 10,500 feet and offer exceptional views, wildlife viewing, and hiking opportunities. Mackay Reservoir, located about ten minutes north of Big Lost River Retreat, covers approximately 1,400 acres and is home to an excellent still water fishery for rainbows and kokanee.

An array of wildlife is found in the area, and hunting and wildlife viewing opportunities are abundant. The extensive riparian corridor along the river, with its cottonwood and willow forests, is a haven for moose, deer, sandhill cranes, raptors, waterfowl, and wild turkeys. Herds of elk are found on adjacent mountains, ridgelines, and foothills. For the upland hunter, chukar partridge are abundant on rocky slopes, while blue grouse are common on the higher-elevation national forest lands. Big Lost River Retreat is located in hunt unit 50 and the Pioneer elk zone.

For hikers and horseback riders, the Lost River area enjoys some of the state’s most spectacular high country. In addition to unlimited cross-country hiking and riding opportunities, an extensive public lands trail network provides access to the area’s vast alpine riches. Mackay is an ATV-friendly community with access to hundreds of miles of motorized trails, some of which lead to historic mining locations and ghost towns, including Mackay Mine Hill, just east of town, where many of the structures have been restored and available for self-guided exploration.