On 19 July 1847, scouts Orson Pratt and John Brown climbed Big Mountain and became the first Latter-day Saints to see the Salt Lake Valley. Because of illness, the pioneer camp had divided into three small companies, and on 23 July the last party, led by Brigham Young, reached Big Mountain, by which time most of the first companies were already in the valley planting crops. Mormons were not the first immigrant group to use this route into the Salt Lake Valley; the Donner Party had blazed the original trail one year earlier and spent thirteen days cutting it from present-day Henefer into the valley, a delay that later proved disastrous when the party was caught in a severe winter storm in the Sierra Nevada Mountains. The Mormons traveled the same distance in only 6 days. Until 1861, this trail also served California gold seekers, the Overland Stage, the Pony Express, the original telegraph line, and other Mormon immigrant companies, after which Parley's Canyon was used.