Marcus Whitman's assistant, William Gray, completed this one-and-a-half-story adobe house for his family in the mission's sixth year. Later it became a guest house and winter quarters for settlers arriving on the Oregon Trail. During the mission period, settlers entering Old Oregon numbered 25 in 1841, 100 in 1842, 800 in 1843, 1500 in 1844, 3000 in 1845, 1500 in 1846, and 5000 in 1847.