From the late 1840s through the 1860s, an exodus of more than 70,000 Mormons passed by here on their way to their "New Zion" in Utah. Starting from Nauvoo, Illinois in February 1846, the first group of at least 13,000 Mormons crossed into Iowa to escape religious persecution, then spent the next winter in the area of present-day Council Bluffs, Iowa and Omaha, Nebraska.In 1847, Brigham Young led an advance party of 143 men, 2 women, and 3 children along the Platte River. At Fort Bridger, Wyoming they departed from the Oregon Trail to head southwest to the Great Salt Lake. Thousands of other Mormons soon followed. Today, a marked 1,624-mile auto tour route closely parallels their historic trek.