Originally a trail through the lands of the Shawnee Indians running west from Westport through present-day Johnson and Douglas Counties, this route was used throughout the 1830's and 1840's by Indians, missionaries, and surveyors. John C. Fremont led one of his famous expeditions west down this road. By the mid 1850's it was known locally as the Westport to Lawrence Road, but from 1856 to the eve of the Civil War in 1860 it was best known as the California Road, as the perils of border guerrilla warfare near southern Johnson County drove emigrant traffic north to this route, which connected to the Oregon-California Trail near Lawrence. In spring 1846, Francis Parkman traveled on what would later be known as the California Road out of Westport to the area near present-day 61st and Knox at Turkey Creek before continuing northwest on the Fort Leavenworth Military Road to Fort Leavenworth and then west on the journey that led to his book The Oregon Trail.