Route Guide - Atlanta and Trinity Lakes
A three-day bikepacking loop in the Boise National Forest highlighting old mining towns, hot springs, alpine lakes, and a 9500' fire lookout. First ridden by IWBP in August 2023.
Overview
The is one of our all-time favorites — a challenging but very fun three-day loop that begins and ends in Pine, and takes you deep into the Boise National Forest. You will skirt the base of the Sawtooth Mountain range, and summit the highest peak of the Trinities. Along the way are beautiful campgrounds, a small town bar, multiple hot springs, river and lake swimming spots, and some of Idaho's best views.
This route is adapted from “Thunder in Paradise,” developed by Boise native Matt Wordell, and featured at bikepacking.com.
Total Route: Approximately 110 miles with 14,000 feet of climbing.
Terrain: Almost all gravel and jeep roads, with just a few miles of pavement. No singletrack.
Recommended Bike and Tires: A hardtail MTB or rigid dirt touring rig would be ideal. 2.2 inch or larger tires for comfort. Those used to “under-biking” on skinnier tires could do ok on a gravel bike.
Suggested Beginning Point: Overnight parking is allowed at a large gravel pullout in Pine, at the intersection of Wood Creek Rd and Lester Creek Rd. There is also a pit toilet here. GPS coordinates 43.483529, -115.311071. Google Maps.
Difficulty *
Climbing scale 8.5/10 (128 feet per mile). Lots of climbing, especially day two. See below for climbing broken down by day.
Technical scale 3/10. Gravel and jeep roads with some stretches that are steep, loose, and less maintained. LONG descents.
Physical demand 8/10. Again, there’s lots of sustained climbing, especially on day two. Elevation up to 9500 feet. Sleep at ~8500 feet. Riders should be in very good to excellent shape, having done several longer rides and long climbs in the preceding month.
Resupply and Logistics 4/10. The route is a loop. Frequent access to water for filtering. Food and limited resupply available day 1 in Atlanta. 6-7 full meals will need to be carried.
Day 1
35 miles / 5000 feet. Begin with a pleasant and flat 10-mile warmup from Pine to Featherville, along the South Fork of the Boise River. Climb to the mostly deserted ghost town of Rocky Bar (please respect private property here by staying on the road), then continue up to James Creek Summit at mile 28. The route then descends 2000 feet to the Middle Fork of the Boise River and into the town of Atlanta at about mile 35.
Atlanta is a historic gold mining town that sits at the base of the the Sawtooths, just on the edge of the wilderness boundary. Highlights include:
Multiple hot springs near town. Visit them all if you have time; our favorite is Chattanooga.
Beaver Lodge restaurant and bar.
The Atlanta School which hosts summer workshops and artists in residence.
Day 1 Camp
Atlanta boasts two nearby campgrounds, Power Plant and Riverside.
Day 2
38 miles / 6000 feet. Eat breakfast in camp or at the restaurant, then cover an easy initial 16 miles down the Middle Fork Road. Then begins the real test of this route — a 20 mile and 6000 foot climb to the Trinity Mountains via Phifer Creek and Trinity Ridge. Water through this area is more sparse and you will need to be prepared to carry more.
Day 2 Camp
Camp at one of the three Trinity Lakes campgrounds. Each is situated on its own small alpine lake, with primitive sites, pit toilets, and a well pump for potable water. No reservations (first come, first served).
Big Trinity Lake Campground — The most popular and first to fill up.
Little Roaring River Lake Campground — Small, with only four spots. Our favorite if you can get a spot. Quiet and beautiful.
Big Roaring River Lake Campground — Also a great campground, with twelve sites, and usually the last to fill up.
Day 3
30 miles / 3000 feet. Wake up early for an optional but absolutely worth it 4 mile / 1000 ft round-trip out-and-back hike to the Trinity Mountain Lookout. Then enjoy a ripping 5000 ft descent to Anderson Ranch Reservoir and back to Pine.
Food and Resupply
We recommend the following general meal plan for a three day pace.
Day 1 trail lunch (no cooking and minimal prep)
Day 1 dinner to prep / cook in camp (in case you miss or decide to skip the lodge)
Day 2 camp breakfast
Day 2 trail lunch
Day 2 camp dinner
Day 3 camp breakfast
Day 3 trail lunch
And of course always carry plenty of snacks
Water
Bring 3-5 liters carrying capacity, depending on the time of year and weather. Day 1 there will be plenty of water available, and you can start off carrying less. But your day 2 water strategy will need a bit more planning. Camp will be near water both nights. Always carry electrolytes.
In addition to the more obvious rivers and lakes, the following are important water spots:
Elk Creek, day 1, mile 22. This comes halfway up the James Creek Summit climb. It's hard to miss, with a beautiful waterfall on the left side of the road. A great lunch spot as well.
Coordinates 43.73230, -115.27500
Spring near Atlanta, day 1, mile 33. On the south side of the road, about 200 yards before the town sign. Locals use this water unfiltered. Fill up as you enter and leave town to save you some filtering time.
Coordinates 43.80303, -115.13513
Spring on the Phifer Creek climb, day 2, mile 59. Don’t miss this one - it’s a great lunch spot, and a key part of making it up this huge climb.
Coordinates 43.751731, -115.341378
Shelter
All of the above recommended campsites would be suitable for a tent, bivy, or hammock.
Route Links
Misc.
Cell service will be mostly unavailable on this route.
Small town business hours can be unpredictable. Call ahead to verify, and carry a simple backup meal in case plans change.
Bikepacking can be strenuous and dangerous. You ride at your own risk.
Please practice the Leave No Trace Seven Principles.
* Difficulty ratings are modeled after bikepacking.com's scale. Ratings are somewhat subjective, and can change based on weather, individual fitness and abilities, and other environmental factors. We welcome input on ratings.