The California Trail was the southern counterpart of the Oregon Trail. When first established, it followed the same route as the Oregon Trail's eastern section until Fort Hall in modern Idaho. At that point, it broke away and crossed desert and mountains to reach California. The first passage was made in 1841 by the Bidwell-Bartleson group. Dividing at Fort Hall, one group made for California with only a general idea that it was to the west. Encountering many obstacles, they abandoned their wagons before reaching California. Later immigrants had the choice of using the Humboldt Valley, which provided better access to water and grass that were essential for the travelers. Although it was easier than the route followed by the original party, the next settlers were again obliged to abandon their wagons. Not until 1844 was a crossing made into California with wagons. Still later, in 1859, the Central Overland route was developed, which shaved ten days off the trip and was 200 miles shorter. U.S. Highway 50 follows a similar route. The California Trail was important in the history of California, because the settlers who did come to California were able to assist John C. Frémont and his American forces to wrest control from Mexico in 1846 and 1847, which was confirmed by the Treaty of Guadalupe Hidalgo in 1848. The trickle of immigrants became a flood after the discovery of gold in 1848. Traffic on the trail continued to be heavy until the completion of the transcontinental railroad by the Union Pacific Railroad and the Central Pacific Railroad in 1869. As with the Oregon Trail, the California Trail was actually a network of trails which adopted alternate routes in many places. In total, around 5500 miles of trails were used, of which about 1000 miles today still show traces of the 19th century wagon ruts. The California National Historic Trail is identified by markers set up by the Bureau of Land Management, the National Parks Service, and many local and state organizations.