A pack horse and livestock trail, the Old Spanish Trail, established by Antonio Armijo in 1829 between New Mexico and El Pueblo de Los Ángeles, joined the Mojave River at its mouth near what is now Soda Lake. It followed the river to where the trail reached the foot of the mountains at Summit Valley and turned westward to pass over Cajon Pass and descend into the coastal valleys of southern Alta California. In 1830, Wolfskill and Yount pioneered what became the Main Route of the Old Spanish Trail, which followed a different route than Armijo, farther south just west of the Colorado River and then followed Jedediah Smith's path on the old Mohave Trail west to the Mojave River mouth at Soda Lake, to meet with Armijo's route coming south from Salt Spring.