The Gilmore and Pittsburgh Railroad (G&P), now defunct, was an American railroad located in southwestern Montana and east-central Idaho. Constructed in 1909 and 1910 between Armstead, Montana, and Salmon, Idaho, the G&P served mining and agricultural areas in Lemhi County, Idaho, and Beaverhead County, Montana. The line was financially backed by the Northern Pacific Railway (NP) and later became its subsidiary. Never financially successful, the G&P ceased operations in 1939, and the railroad was dismantled the following year. Planning and construction During the first decade of the 20th century, Lemhi County, in the remote Salmon River country of central Idaho, was seeing both increased agricultural development and substantial, renewed mining activity. At that time, the area was part of one of the largest contiguous blocks of land not served by a railroad and, consequently, there was significant interest in the prospect of building a railway line to serve the region. The desire for a railroad was perhaps most strongly felt by those promoting the county's mining developments, although a variety of existing railway companies also studied the prospects of the area. The NP gave Lemhi County particular attention, envisioning a new transcontinental route that would veer southward from their existing lines in Montana, cross into Idaho via Bannock Pass, and follow the rugged Salmon River canyon westward across the state. These dreams began manifesting in 1907 when a group of Pennsylvania businessmen led by W. A. McCutcheon incorporated the Gilmore and Pittsburgh Railroad. McCutcheon envisioned a railroad running westward from a connection with the Oregon Short Line Railroad at Armstead, Montana. The line would enter Lemhi County via Bannock Pass, and continue to the Lemhi River valley. In the valley, branch lines would run upstream to the promising mining camp of Gilmore, and downstream to the county seat of Salmon. Soon, McCutcheon was able to interest NP officials in his plan, since a completed G&P could form a basis for a future NP line down the Salmon River. The NP assisted in the initial survey of the G&P route, and later agreed to financially and materially support the G&P's construction. A contract for construction of the G&P grade was awarded in March 1909, and work began in earnest the following month. Construction was pursued in earnest throughout the following year, working west from Armstead, and the tracklayers reached Salmon on April 25, 1910. The completed line was in length, and