This route from Boonville to Sedalia was used long before the Katy Railroad. In 1820, founders named this place Pilot Grove because a local grove of trees guided travelers along the divide between the Lamine River and Petite Saline Creek. Paths from here led northeast to the Missouri River and in the other direction to Osage villages in southwest Missouri. After 1821, the Osage trail became busier as it connected the growing settlement of Franklin with the newly built Harmony Mission near the Osage villages. In 1825, a treaty moved the Osage to Kansas, and they left their villages in Missouri. Soon afterward, the Boonville-Georgetown Trail passed through Pilot Grove. Before railroads made Sedalia the transportation hub of Pettis County, Georgetown was the county seat from 1837 to 1865. During the Civil War, Union Gen. Nathaniel Lyon and 2,400 troops marched southwest along this route in July 1861 after taking Boonville from the Confederates. On Aug. 10, Lyon's troops fought a force twice as large under Gen. Sterling Price at the Battle of Wilson's Creek near Springfield, where the Confederates won and Lyon became the first Union general killed in the Civil War. The Missouri, Kansas & Texas Railway later built its first line from Sedalia to Fort Scott, Kan., then turned toward Boonville and the Missouri River, and tracklayers reached Pilot Grove on May 18, 1873. Travelers continued to share this route because it followed ridgelines, often crossed open prairie with good visibility, avoided repeated stream crossings and thick forest, and provided essential water along the way.