Bonner and nearby communities grew at the meeting of the Blackfoot and Clark Fork rivers as the Northern Pacific Railroad arrived in 1883, drawing loggers and millworkers from many places, while E.L. Bonner had anticipated the boom in 1881 when Eddy, Hammond and Company won the lumber contract for building the railroad; by 1886 the Bonner mill was operating and a company town had been established, the Anaconda Company took over the mill in 1898 and remained until 1972, and residents maintained an independent tradition shown when the Industrial Workers of the World camped across the tracks along the Clark Fork River in 1914 and successfully pressed for better housing and food, and when mill employees organized a labor union in 1942. In the summer of 1806, Lewis and Clark were returning east from the Pacific, and on July 3 they split at Traveler's Rest; Clark headed toward the Yellowstone River, while Meriwether Lewis, with nine men and his dog Seaman, followed a Nez Perce route up the Blackfoot River from July 3-7, crossing quickly over the Continental Divide toward the Missouri River, recording wildlife and mountain country along the way, passing five deserted Indian encampments, and on July 6 joining fresh tracks that appeared to be from a returning Blackfeet war party, which heightened his caution. Flowing 132 miles from the Continental Divide to its confluence with the Clark Fork, the Blackfoot River has long been a corridor for both people and wildlife, shaped by Ice Age valleys and pothole lakes and bordered by habitat for osprey, great blue heron, Canada geese, bald eagles, and native trout; its human history includes late nineteenth-century logging for railroad ties and mine shafts, spring log drives to the Bonner sawmill until the mid-1920s, and continued use today by ranchers, boaters, anglers, and the small communities that retain strong ties to their heritage.