In late July 4, 1846, a party of 15 men called the South Road Expedition, led by Capt. Levi Scott, Jesse Applegate, and David Goff, crossed the 42nd parallel while blazing a road intended to lead Americans away from danger from an impending war with Great Britain. Mexico lay to the south and had been at war with the United States since May 13, 1846, but Great Britain and the U.S. signed a treaty on June 15, 1846, setting Oregon's north line at latitude 49 north. Scott's party had left Rickreal Creek on June 20 and heard of the treaty at Fort Hall. Because no war began with the British, the route they blazed eastward served as a wagon road for immigration to Oregon. On Feb. 2 1848, the large Mexican cession was added to block up the western United States. The road later became the scene of more Indian-white killings than all other western routes combined. This point was recorded by U.S. Surveyor Daniel Major, who, while running the state line from his own 120th meridian, triangulated over Lower Klamath Lake on Nov. 5, 1868, noting “93m-66.5ch crossed emigrant road to Jacksonville,” and that point lies under the monument.