Beginning on May 22, 1843, nearly one thousand Americans left Missouri for new lives in the Oregon Country, and during the next two decades more than 50,000 emigrants traveled the more than two-thousand-mile Oregon Trail toward the land Abigail Scott called the "Garden of the World." Along this hard route, the fragile landscape was strained by increasing traffic, and privation, illness, and death often afflicted travelers. Fort Boise, built by the Hudson's Bay Company across the Snake River in 1838 to oppose the American trading post at Fort Hall, served as an oasis where emigrants in the 1830s could find hospitality, assistance from local Indians, and provisions under the care of clerk Francois Payette. By the mid-1840s, however, depleted beaver populations and the decline of the fur trade brought Fort Boise and Britain's claim to the Oregon Country into rapid decline, and by the early 1850s many emigrants found the post dilapidated and poorly supplied. The nearby Snake River crossing remained one of the trail's great obstacles, where emigrants, wagons, and livestock all had to cross and casualties were common, though local Indians could often be hired to help swim animals across. By 1853 a newly established ferry eased wagon passage, replacing earlier methods that relied on a fort canoe and careful balancing of wagon and load. The crossing also figured in the larger story of overland migration, for when Marcus and Narcissa Whitman left their wagon at Fort Boise in 1836, it stirred excitement in the States by suggesting that wagon emigration to Oregon was possible.