The Mullan Military Road was the project of Army Capt. John Mullan, to create an important link between frontier forts in the West, as well as a long-envisioned connection between the Missouri and Columbia rivers to unite the continent. Although the work was to begin in 1858, confrontations with Native American tribes prevented the beginning of construction until 1859.

The 624-mile road from the military fort in the town of Walla Walla to Fort Benton on the Missouri River began with an existing leg from old Fort Walla Walla on the Columbia River at Wallula. This early road had been established as a well-used branch of the Oregon Trail, passing through the Whitman Mission, just west of present-day Walla Walla. 

On July 1, 1859, Mullan and his company of 100 soldiers and 100 workers departed from Walla Walla in Washington Territory to begin construction of the new road between Fort Walla Walla and Fort Benton in what later became Montana Territory. From Walla Walla the road passed near present-day Prescott on its way to the Snake River. In 1859 the road crossed the Snake at the mouth of the Tucannon River, but by 1861 the crossing had been moved to Lyons Ferry. From there the road went northeast, originally passing south of Lake Coeur d’Alene and, after additional work in 1861, passing near present-day Spokane, then crossing into Idaho near what is now Post Falls. From there it made its way to present-day Missoula, Mont., before climbing to its highest elevation at Mullan Pass (5,168 feet). The road went north of the current city of Helena, through present-day Great Falls and on to Fort Benton on the Missouri River.

The total cost of construction of the road was $230,000. Building the road involved myriad  tasks, including the removal of rocks and trees, choosing or fashioning reasonable grades and building dozens of bridges. Upon its final completion in 1862, it became the first wagon road to cross the Rockies to the Inland Northwest and ensured the future of the fledgling settlement of Walla Walla.

Although conceived as a military road, in the end the Mullan Road proved to be far more important to settlers, tradesmen and gold miners than for military use. Even during construction, Mullan and his men found “continual indications of gold” in Montana. By the time the crew were making improvements and repairs to the road as they worked their way back to Walla Walla from Fort Benton in 1860, parties of emigrants were already overtaking them. Many new settlers traveled to Fort Benton by steamboat up the Missouri, where they picked up the new road. At its end they could board a steamboat on the Columbia River at Wallula. 

Despite the promise of the Mullan Road, it proved to be difficult to maintain. Shortly after its completion, it was in such disrepair that only foot travelers and pack animals could follow its course, especially through the mountains. Still, the settlers came, and in 1862 Walla Walla was already prospering as a stopover and was bustling with commerce and construction. Mullan wrote: “The wilderness of yesterday has to-day given place to homes.” In spite of conditions, the Mullan Road was well-traveled until the railroads supplanted the overland trails. 

Today, the Mullan Road is still visible in a number of locations. Traces can be seen not far from Walla Walla at Lyons Ferry and near Washtucna. The Mullan Road was an integral part of the fastest land-water route across the American continent. Traversing the Mullan Road took about 47 days, a far cry from today’s 10-hour highway trip over the same route. 

As part of the effort to give the road the recognition it deserves, efforts have been made to commemorate it through interpretive signs, monuments, conferences and on the Web. In April, a historical site commemorating the road was dedicated along 13th Street at Abadie Street in Walla Walla. 

You can learn more about the Mullan Road at

Mullan’s original map can be viewed at

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