Las Vegas began at this site on June 14, 1855, when thirty-two Mormon missionaries from Utah under William Bringhurst arrived. That summer they established farm fields, and in September began building a 150-foot-square adobe fort enclosing eight two-story houses. They cultivated small gardens and fields, planted fruit and shade trees, and tried to convert the local Southern Paiutes. Most of the Mormons departed in 1857, and in 1865 Octavius Decatur Gass began developing the Las Vegas Rancho, using the adobe structures as headquarters. He farmed and raised beef cattle, supplying travellers and miners in the Potosi region. Helen J. Steward, who owned the property from 1882 to 1902, expanded the ranch to 1,800 acres, then sold it to the San Pedro, Los Angeles and Salt Lake Railroad for the Las Vegas townsite. The company auctioned the land on May 15, 1905, beginning the process of building the Las Vegas of today.