At a watering hole on the east side of Pacheco Pass, Juan Pacheco built an adobe for his rancho in the early 1840s. Gun ports in its walls remained as reminders of dangers from Yokuts Indians, marauding bands of ex-Mission Indians, and bandits emerging from the San Joaquin Valley, on what was then the frontier of Mexican California. Paula Fatjo, descendant of the Pachecos and the Malarins and heir to Rancho San Luis Gonzaga, restored the adobe as her home and ranching headquarters in 1948. A San Francisco society belle, she returned to the family rancho to live the life of her ranchero ancestors. In the 1960s, the Central Valley Water Project took about half the rancho, including the site of the ranch headquarters and the adobe. Paula built a new ranch headquarters on the western portion of the rancho, but she would not leave the old family adobe to be melted away by the flooding waters of the San Luis Reservoir. It was the oldest adobe in the San Joaquin Valley. She built new foundations at this location and had the adobe structure lifted onto a truck to be transported here, but as it came up the hill, the truck shuddered at the last moment and the side walls of the precarious adobe came tumbling down.