Between 1840 and 1869, approximately 500,000 emigrants traveled through the Casper area on three National Historic Trails: The Oregon Trail, the Mormon Trail and the California Trail. They migrated for different reasons: They sought free land in the Oregon Territory, religious freedom in the Great Salt Lake Valley, and free gold in California. These pioneers left behind not only trails, but important stories as well, stories that are significant to U.S. history.