The

Lewis and Clark

Back Country Byway

and Adventure Road

Tendoy, Idaho 

1

The

Lewis and Clark

Back Country Byway

and Adventure Road

Tendoy, Idaho 

The Lewis and Clark Back Country Byway and 

Adventure Road is a 36 mile loop drive through a 

beautiful and historic landscape on the Lewis and 

Clark National Historic Trail and the Continental 

Divide National Scenic Trail. The mountains, 

evergreen forests, high desert canyons, and grassy 

foothills look much the same today as when the 

Lewis and Clark Expedition passed through in 

1805.
Getting There

The portal to the Byway is Tendoy, Idaho, which is nineteen miles 

south of Salmon on Idaho Highway 28. From Montana, exit from 

I-15 at Clark Canyon Reservoir south of Dillon onto Montana 

Highway 324. Drive west past Grant to an intersection at the 

Shoshone Ridge Overlook. If you’re pulling a trailer or driving 

an RV with a passenger vehicle in tow, it would be a good idea 

to leave your trailer or RV at the overlook, which has plenty of 

parking, a vault toilet, and interpretive signs. Travel road 3909 

west 12 miles to Lemhi Pass. Please respect private property 

along the road and obey posted speed signs. Salmon, Idaho, 

and Dillon, Montana, are full-service communities. Limited 

services are available in Tendoy, Lemhi, and Leadore, Idaho and 

Grant, Montana.

Traveling the Byway is a Real Adventure!

•	 The Byway is a single-lane gravel road with pullouts. 

Passenger vehicles can drive the road safely but must 

have good tires. Buses, RVs, and trailers are not 

recommended on the Agency Creek Road [see map], 

which is narrow and has some tight corners. Even if 

you’re experienced in mountain driving, drive slowly and 

carefully. 

•	 There are three segments to the Byway. First is the “Lemhi 

back road” in the Lemhi Valley near Tendoy. Second is 

the “Warm Springs Wood Road” [185] from the valley 

into the Beaverhead Mountains to Lemhi Pass. The third 

segment is the Agency Creek road [013] from Lemhi Pass 

back to Tendoy.

•	 With a 4,000 foot gain and loss in elevation, expect 

some steep grades, at times approaching 20%. A hard 

climb on a hot day can cause your vehicle engine to 

overheat. Shift into low gear, turn off the air conditioning 

2
and open your windows. 

•	 The Byway is normally free of snow from early June 

through October. To check on current road conditions 

call the Public Lands Center in Salmon at (208) 

756-5400.

•	 There are numerous opportunities for hiking and 

mountain biking. At lower elevations, be alert for 

rattlesnakes.

•	 Cell phone coverage is sporadic at best. 

•	 The remains of mining operations are scattered 

throughout the area. These sites can be very hazardous. 

Stay out, and stay alive.

•	 Plan on taking a minimum of three hours to drive 

the Byway. Drive carefully and slowly, even if you’re 

accustomed to mountain driving. Parts of the Byway 

traverse steep, exposed slopes and there are no 

guardrails.

Checklist for a Safe and Enjoyable Journey

At least half a tank of gasoline

A properly inflated spare tire, jack, and lug wrench

Drinking water; water from springs and streams must be 

chemically treated or filtered

First aid kit

Extra food

Sweater and rain gear; it can snow year-round at 8,600 

feet elevation

Flashlight

Camera and film, binoculars

Books to identify birds and wildflowers

3
Mule Deer

Antlers

Meadowlark

Syringa

4
Scenic Attractions

The Byway traverses four habitats: river valley, sagebrush 

grasslands, mountain forests and meadows, and high desert 

canyons. The views of the Lemhi Valley and the surrounding 

mountain ranges are incredible. This is truly some of the finest 

scenery in America. Wildflowers are prolific in spring and 

summer. Early mornings and evenings are the times to look for 

wildlife, particularly where forest and meadow meet. You might 

see elk, mule and whitetail deer, black bear, moose, pronghorn 

antelope, coyotes, and many smaller mammal species. 

Among the many bird species present are golden eagle, redtailed hawk, chukar, hungarian partridge, blue grouse, sage 

grouse, nighthawk, mallard duck, Canada goose, great blue 

heron, mourning dove, boreal owl, four hummingbird species, 

belted kingfisher, flicker, Lewis’ woodpecker, magpie, Stellar’s 

Jay, Clark’s nutcracker, chickadee, tree swallow, robin, blue 

bird, cedar waxwing, Western tanager, song sparrow, Western 

meadowlark, Brewer’s blackbird, and American goldfinch.

Wildflowers bloom in spring and summer, their presence varying 

according to weather, elevation, and each species’ characteristic 

requirements. Lemhi Pass is well-known for its wildflower 

displays. Captain Lewis collected three new plant species in 

this area: mountain maple, common snowberry, and Lewis’s 

monkey flower. You may also see desert buckwheat, sunflowers, 

arrow-leaf balsamroot, buttercups, glacier lilies, larkspur, sticky 

geranium, sego lily, lupine, forget-me-not, yarrow, bitterroot, 

phlox, spring beauty, blanket flower, asters, violets, paintbrush, 

currants, evening primrose, yellow monkey flower, valerian, flax, 

blazing star, serviceberry, and syringa.

By late September shorter days and cooler temperatures release 

hues of red, yellow, and gold in aspens, cottonwoods, willows, 

and shrubs. Agency Creek is beautiful in October.

5
Shoshone fish weir on the Lemhi River, 1906 —Smithsonian Institution

Shoshone man fishing on the Lemhi River, 1906 —Smithsonian Institution

6
Native Americans

The Lewis and Clark Expedition did not blaze new paths 

here. They followed long-established Indian trails. This is 

the homeland of the Agai Dika [“salmon eater”] Shoshone, 

who came to be known as the Lemhi Shoshone after the 

Mormon settlement of Ft. Lemhi was established in the 1850s. 

Archaeological evidence suggests that the Shoshone may have 

arrived possibly 3,500 years ago. The chinook and sockeye 

salmon that returned here from the Pacific Ocean every summer 

to spawn were at the center of Lemhi life and culture. 

Early in the 18th century the Lemhi acquired horses, which greatly 

increased their standard of living. The men used horses to hunt 

bison and to transport a winter’s supply of bison “jerky” to winter 

campsites. Women tanned bison hides and sewed them together 

to make tepees, which were hauled by horses wherever the 

family went. 

Hunting bison took the Lemhi onto the game-rich plains of 

central Montana, where they came into conflict with other 

tribes. When their enemies the Blackfeet, Atsina, and Hidatsa 

acquired firearms from Canadian traders in the late 18th century, 

the Lemhi retreated to their mountain homeland. An annual 

bison hunt was still conducted, often with allies such as the 

Salish [Flatheads], Nez Perce, and Crow tribes. Sacagawea was 

kidnapped by the Hidatsa during a bison hunt around 1800. 

She was taken to the Knife River villages in North Dakota, where 

she and her husband Charbonneau joined the Lewis and Clark 

Expedition.

Fur traders and trappers eventually reached the Lemhi Valley, 

then missionaries and finally miners and settlers. The Lemhi, now 

including Sheepeater and Bannock families who had joined the 

Shoshone, remained peaceful, but found it increasingly difficult 

to hunt, fish, and gather food in their traditional manner. 

7
Fanny Silver was born on the Lemhi Reservation near Tendoy about 1897. She was at 

boarding school in Fort Shaw, Montana when the Lemhi Shoshone were moved to Fort 

Hall in 1907. Her family returned to the Lemhi Valley to hunt , fish and gather plants 

in the traditional manner.. Silver died in 1985 when she was eighty eight years old.

—Photography by Jed Wilson, 1971

8
President U. S. Grant authorized a small reservation for the 

Lemhi tribe in the 1870s, but the federal government pressured 

the tribe to move south to a central Shoshone Bannock 

reservation at Fort Hall in 1907.

The Lewis and Clark Expedition

In August 1805 the Lewis and Clark Expedition reached the 

headwaters of the Missouri River. Lewis set out on foot with a 

small party to find the Shoshone, Sacagawea’s people, whose 

horses he hoped would help portage the Expedition’s baggage 

over the divide. But the mountain barrier he saw to the west 

from Lemhi Pass suddenly complicated the mission. Could there 

be a navigable river through such mountains? If not, then the 

Expedition must buy horses. If they could not find the Shoshone, 

or if the tribe refused to sell, the Corps of Discovery had only 

one option: return down the Missouri. Nothing less than the 

success of the Expedition, and the future of the United States, 

were at stake. 

Euro-American Settlement

Trappers, explorers, and missionaries followed in the wake of 

the Lewis and Clark Expedition. Permanent settlement began in 

the 1860s when gold was discovered in the nearby mountains 

and miners arrived. The Lemhi Valley was bracketed by the towns 

of Salmon City at the mouth of the Lemhi River and Junction at 

its headwaters. The valley and its major tributaries were soon 

occupied by ranchers and farmers, many of whose descendants 

still live here today. 

The land that was not claimed by settlers was eventually brought 

under the management of the United States Forest Service and 

the Bureau of Land Management. 

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10

LOCATION MAP

MAP LEGEND 

P a t t e e C r e e k

P a t t e e C r .

Warm Springs Cr.

F l u m e C r .

K e n n e y

C r e e k

S a n d y C r . K a d l e t z C r e e k

P r i c e C r e e k

B a l d y C r e e k

P r a t t C r e e k

A g e n c y C r e e k

A g e n c y C r e e k

W h i t e C r .

S h a r k e y C r .

C o w C r e e k

Y e a r i a n

C r e e k

S. Fork Yearian Cr,

M c D e v i t t C r e e k

Lem

hi River

28

Lemhi

Baker

Tendoy

IDAHO

Lewis

and Clark

Backcountry

Byway

Salmon

Mile 31.5

Agency Creek

Campground

Mile 0.2

Mile 9.6

Pattee Creek 

Overlook

Mile 3.5

Back Country

Byway Kiosk

Mile 24

Lemhi Pass

National Historic Monument

Mile 25

Mile 26

Mile 8.2

Flag Unfurling

IDAHO MONTANA

Lewis’s

Aug.12, 1805

Clark’s Campsite

Aug.19, 1805

Campsite

Salmon

Leadore

Picnic Area

Mile 4.8

Sharkey

Hot Springs

Back Country Byway Route

State Highway

Other Road

National Historic Trail

Town

Point of Interest

View

Camping

Information

MAP SCALE:

0 3

Miles
Byway and Adventure Road Mileages

Although the mile guide is written in a clockwise direction, 

the Byway can be traveled in either direction. Mileages are 

approximate and will vary depending upon the eccentricities of 

your vehicle’s odometer.

Mile 0—Tendoy

The “portal” to the Byway was named for Tendoy, head chief of 

the Lemhi Shoshone from 1863 to 1907. His strong leadership 

kept his tribe at peace and earned him great respect from local 

settlers. Tendoy successfully resisted Federal government pressure 

to move his people to the Fort Hall reservation near Pocatello 

until he died in 1907.

The first Tendoy store and post office was built in 1911. Its 

remains stand behind the present store.

Mile 0.2—“T” intersection

Turn left onto what is referred to locally as the “Lemhi back 

road.” 

Mile 1.5—Sunfield

This area was homesteaded by Joseph B. Pattee, the last 

manager of Hudson’s Bay Company Fort Hall trading post. A 

post office and school were built in the early 20th century. 

Mile 1.8—Fort Lemhi

In 1855 a party of twenty-seven Mormons arrived in the Lemhi 

Valley to establish a mission among the Shoshone, Sheepeater, 

and Bannock tribes for the purpose of converting and “civilizing” 

them. The missionaries built both a fort with cabins surrounded 

by a nine foot high log palisade and an adobe livestock corral. 

At first relations with the local tribes were cordial, but tensions 

arose, particularly with the Bannock. More Mormons arrived 

and a second fort was constructed, signs that the mission station 

11
was becoming a permanent colony. Bannock resentment and a 

series of misunderstandings led to a raid on the fort’s livestock 

on February 25, 1858. Bannock warriors drove off most of 

the Mormons’ cattle and horses. Two missionaries were killed 

and five wounded. A month later the Mormons abandoned 

their settlement and returned to Utah. The only visible remains 

today are portions of the corral wall. Please respect the private 

property upon which they stand.

The fort was named for Limhi, a king in the Book of Mormon. 

The spelling was changed to Lemhi and the name applied to the 

river, mountain range, and pass.

Mile 3.0—Turn right to leave the Lemhi back road and continue 

on the Byway along the “Warm Springs Wood Road [185].

Lewis meets women, gives trinkets —Delbert Farmer, Fort Hall

Mile 3.5—Backcountry Byway Kiosk

Here you will find Byway information, interpretive panels, picnic 

tables and vault toilets.

12
In this area Captain Lewis’s advance party first made contact 

with the Lemhi Shoshone on August 13, 1805, when they 

suddenly came upon three Shoshone women. After “pacifying” 

them with gifts, Lewis persuaded the women to take the explorers 

to their encampment to speak with the chief. On the way there 

they met the chief and sixty of his warriors, who had been alerted 

to the presence of possible enemies by Shoshones who had seen 

Lewis’s party. When the women showed Chief Cameahwait the 

gifts Lewis had given them, he welcomed the four strangers as 

friends.

Mile 4.0—Intersection

Go left to continue on the Byway. Or, turn right for the Alkali Flat 

road, which follows roughly the route of the Lewis and Clark Trail 

toward Pattee Creek. This dirt road can be impassable when 

wet; use caution. Look for posts with the Lewis and Clark Trail 

emblem. 

Sharkey Hot Springs recreation site —BLM Photo

13
Mile 4.8—Sharkey Hot Springs is named for pioneer miner and 

rancher Frank Sharkey, this BLM recreation site features two 

large outdoor soaking pools, changing rooms, vault toilets, a 

fire pit and picnic tables. This is a recreation fee site.

Mile 8.2—The Flag Unfurling Monument commemorates the 

display of the U. S. flag by Lewis’s advance party on August 13th, 

1805. This symbolic act introduced a new nation to the Lemhi 

Shoshone and strengthened the American claim to the

Northwest. This was the first time the Stars and Stripes were 

unfurled in present-day Idaho.

Mile 9.6—Pattee Creek Overlook provides a hawk’s eye view of 

Pattee Creek from its steep forested canyon on the left through 

the grassy foothills to the front. A detachment led by William 

Clark camped on lower Pattee Creek below on the night of 

August 19th, 1805, on their way to assess the navigability of the 

Salmon River. [The river proved to be unnavigable.]

across the head of hollows and Springs....

Captain William Clark, August 19, 1805

The high peaks of the Lemhi Range lie to the southwest. 

Opportunities for hiking, fishing, and other types of recreation 

abound in these mountains. 

Mile 10.3—The Salmon-Challis National Forest

As you climb from the steep slopes of the Pattee Creek canyon 

to its headwaters near the Continental Divide, you’ll see tree 

species typical of the northern Rockies. Douglas fir dominates 

the lower elevations, giving way to lodgepole pine, subalpine fir 

and whitebark pine nearer the Continental Divide. Engelmann 

spruce is found in wet areas. Evidence from timber and logging 

sales is apparent, but there are also stands of “designated old 

growth,” including the north-facing canyon wall of Pattee Creek 

to your right.

14
Lewis and men meet Shoshone on horseback —Adolph DeVinney, Fort Hall

Aspen, a species with great wildlife value, have all but 

disappeared in this section of the byway. The philosophy of 

aggressive wildfire-suppression that prevailed in the 20th century 

permitted the encroachment of Douglas fir and other conifers 

into aspen stands. Historically, wildfires both removed competing 

conifers and stimulated the growth of new aspen trees (actually 

“suckers”) from their extensive root systems. Land managers 

have begun to implement strategies to restore aspen stands. 

At the beautiful meadows that are the headwaters of Pattee 

Creek, the road turns south to contour near the Continental 

Divide for several miles. Congress designated the 3100 mile 

long Continental Divide National Scenic Trail in 1978. Every 

year a handful of “thru-hikers” complete the entire distance. 

The rolling, densely forested terrain in this area contrasts with 

the alpine lake country to the north and the broad-shouldered 

mountain and range country south of Lemhi Pass.

15
Westward view from Lemhi Pass —BLM Photo

Mile 23.5—Lemhi Pass National Historic Landmark

This site features an overview of the Indian route the Lewis and 

Clark Expedition followed westward. To reach Lemhi Pass, turn 

left [north] as you exit the parking lot. Hikers can follow the 

ridgeline south to Lemhi Pass along the Continental Divide Trail. 

The 480 acre Landmark was designated in 1960. Parking and a 

vault toilet are accessible here. 

Mile 24—Lemhi Pass (We-yah-vee) 

Please use the parking area 500 feet north of the pass on the 

Montana side [Road 3909], which has an information kiosk, 

vault toilet, and visitor register box. An accessible interpretive 

trail leads back to a stone monument at the pass. 

16
Lemhi Pass History

. . .we proceeded on to the top of the dividing ridge from which I 

discovered immence ranges of mountains still to the west of with their 

tops still partially covered with snow*.

Captain Meriwether Lewis, August 12, 1805. 

Lewis and the other men in his advance party, John Shields, 

George Drouillard, and Hugh McNeal, were expecting to leave 

the Rocky Mountains behind them when they reached this ridge. 

Imagine their thoughts as they discovered how wrong they were. 

With determination, luck, and diplomacy, they proceeded on 

to find and befriend the Shoshones who would sell them the 

horses they needed to portage this pass and cross the Bitterroot 

Mountains to navigable waters on the Clearwater River.

The Shoshones called the pass We-yah-vee. They and other 

tribes had used it for many generations before the Corps of 

Discovery arrived in 1805. Lewis and Clark gave the pass no 

name, but during the fur trade decades that followed it was 

known as “North Pass,” to distinguish it from South Pass in 

Wyoming. Several battles were fought near the pass during that 

time. In 1823 Hudson’s Bay Company trappers led by Finan 

McDonald defeated a party of Blackfeet. Blackfeet massacred a 

Salish party near here in 1832.

Horse and mule pack trains crossed the pass regularly after 

the 1866 Leesburg gold rush brought permanent settlement to 

the Salmon River country. When the Utah & Northern railroad 

reached Dillon, Montana, in 1880, the citizens of Salmon 

pooled their resources to build a road over the pass to the Red 

Rock rail station south of Dillon. Known first as the Ft. Lemhi and 

Montana Wagon Road, it became the Red Rock-Salmon City 

Stage Road when stagecoach service began in the late1880s. 

17
$8.00 bought a one-way ticket for the twelve hour trip from 

Salmon to Red Rock. Stations along the way provided meals 

and fresh mules and horses. The stage company employed 

from 35-40 people and operated up to fourteen coaches and 

a dozen freight wagons. It carried several thousand passengers 

and hauled over a million tons of freight over the pass each year 

until 1910, when the Gilmore and Pittsburgh RR was completed 

over Bannock Pass to Salmon. Since then most visitors to Lemhi 

Pass arrive in automobiles.

Lemhi Pass Fault Zone (arrow) and thorium prospects —BLM Photo

Lemhi Pass Geology

Lemhi Pass exists because it straddles a fault zone characterized 

by broken and fractured rock that erodes more rapidly than the 

surrounding rock, creating the low “saddle” that offers an easy 

crossing of the mountain range. 

18
The area around the pass contains one of the world’s largest 

deposits of thorium, a radioactive mineral that attracted great 

interest in the past because it produces two times the energy as 

the same size unit of uranium and creates fewer hazardous byproducts. Thorium prospectors have left behind roads, trenches 

and pits, which can be hazardous and should be avoided. Dust 

particles containing thorium that are inhaled or ingested in 

sufficient quantities can damage body tissue and lead to cancer.

What remains of the Withington Caldera (approximately 3.6 

miles wide) can be seen to the northwest at the northern terminus 

of the Lemhi Mountains. Greenish ash-flow tuff blasted from 

this volcanic explosion about 48 million years ago can be seen 

cropping out at several places along the Agency Creek road 

below the pass.

Sacajawea Sees the Beaverhead —Jill W. Hastings, Fort Hall

The Sacajawea Memorial Area (Montana Side of Lemhi Pass)

Located 0.2 mile south of the pass on the Montana side, this 

Forest Service site created through the efforts of Laura Tolman 

Scott of Dillon honors the Lemhi Shoshone woman who served 

the Expedition as an interpreter. There are vault toilets, picnic 

tables, and an interpretive trail.

19
Agency Creek Road [No. 013] heading west off of Lemhi Pass

The first two miles of this road are very steep and narrow with 

several blind corners. It is not appropriate for trailers, buses, or 

motorhomes. Use you lowest gear and exercise great caution. If 

you meet another vehicle, back uphill to the closest pullout and 

allow them to pass.

Mile 25.0—Horseshoe Bend Creek

Lewis and his men drank from this creek where it joins 

Agency Creek 0.4 mile below this sharp curve. They consoled 

themselves following their shocking view from Lemhi Pass with 

the belief that they were drinking from a stream that would 

eventually reach the Columbia River.

Mile 26.0—Trail Crossing

The Lewis and Clark Trail climbs from Agency Creek on the 

left into the steep grassy draw to the right. Whenever possible, 

Indians in this area seem to have avoided travel through narrow, 

brushy canyons, which were both difficult for horses pulling 

travois and excellent places to stage an ambush. 0.2 of a mile 

up this draw, the Trail turns west into the lower Flume Creek 

basin. Lewis’s advance party camped on the night of August 12, 

1805, at a spring west of Flume Creek (see photo below).

20
Mile 27.5—Flume Creek at Ghould Basin Road along the Red 

Rock Stage Road.

The Flume Creek/Ghoul Basin side-tour provides access 

to the Lewis and Clark Trail from the Agency Creek Road. 

This tour is for 4WD, high clearance vehicles only. Wet 

weather can make the route impassable.

Mile 0—intersection with Byway.

0.6 miles—intersection with Lewis and Clark Trail, which 

comes in from the right [east] and continues down to a 

ford of Flume Creek. Park here and continue on foot. 

0.8 miles—ford Flume Creek. From here it’s about 3⁄4 of 

a mile to Lewis’s 1805 campsite and a 500 foot climb.

1.4 miles—on the left is one of two springs that are likely 

candidates for the campsite of Meriwether Lewis, George 

Drouillard, John Shields, and Hugh McNeal on the night 

of August 12, 1805. This was the first time American 

citizens had slept in present-day Idaho. Because they had 

killed nothing that day, their supper was a piece of salt 

pork that had traveled with them from Illinois. 

the Indain road...lead us over steep hills and deep hollows to a 

spring on the side of a mountain where we found a sufficient 

quantity of dry willow brush for fuel, here we camped for the 

night....

Captian Meriwether Lewis, August 12, 1805

The pleasant little spring would also serve as a temporary 

rest area during the later portage over Lemhi Pass on 

August 15th and 26th, 1805.

Mile 2.0—the second possible spring campsite.

21
Continuing on the Byway, the Cold Springs Stage Station was 

located in the Agency Creek bottom to the left.

Mile 27.7—Flume Creek

Secluded valleys such as this were favored winter retreats of the 

Shoshone. They provided water, firewood, and protection from 

wind. Horses could graze dried grasses on the surrounding 

mountains and nibble slender twigs from trees along the 

streams. Agency Creek supports small numbers of rainbow and 

cutthroat trout.

Mile 30. 4—ranch yard

Please observe 15 mph speed limit. Much of the land along 

Agency Creek is privately owned. Please respect property rights. 

Mile 31.5—Agency Creek Campground

This is a small, somwhat primitive campground that provides 

room for approximately four campsites. The campgound has 

a vault toilet, interpretive signs, and is always full during the fall 

big game season.

Mile 32.0—Cow Creek Road

Mile 35.6—“T” intersection with Lemhi Back Road

Turn right.

Mile 35.7—Tendoy School

Mile 35.8—Intersection

Turn left to return to Tendoy.

Mile 36.0—Tendoy

22
Agency Creek Campground —BLM Photo

 Chief Tendoy and his

 son, Yoho, near

 Leesburg in 1896

 —Photography 

 O.E. Kilpatrick

23
Objects of Curiosity 

All Artwork: Shoshone-Bannock Tribal Museum, Fort Hall, Idaho 

Cover: Sunset below Lemhi Pass, Glenn Oakley 

24
—Evelyn Teton, Fort Hall

Inside Cover: Meriwether Lewis’s journal, August 18, 1805, 

American Philosophical Society, Philadelphia.
The Public Lands Center in Salmon, Idaho

Salmon-Challis National Forest / BLM Salmon Field Office

1206 S. Challis Street / Salmon, ID 83467 / (208)756-5400

BLM/ID/GI-08/006+1220