This paper explores the history and geography of the Milwaukee Road corridor in eastern Washington state. The corridor was originally built for rail traffic in the early 1900s, and its history is a complex story full of visionaries, innovation, legal challenges, and financial misfortunes. For much of the twentieth century, the corridor served as an important transportation line between the upper Midwest and the Pacific Coast. Abandoned as a railroad in 1981, most of the corridor within its borders is now owned by the state of Washington and is essentially railbanked under state legislation. It is currently used as a nonmotorized recreational trail, providing a unique opportunity for hikers, bikers, skiers, wildlife watchers, equestrians, and wagon trail riders to travel across the state of Washington. Along the way, travelers encounter remnants of the historic built environment of the state. In addition, the Milwaukee Road traverses the unique and diverse physical geography of eastern Washington, extending from the Cascade Mountains across the Columbia Plateau to the Idaho border. A journey along the Milwaukee Road corridor tracks the evolution of land use in eastern Washington throughout the twentieth century and into the twenty-first. As such, it serves as an important and unique pathway through the history and geography of eastern Washington.