Less a utopian community than a health-oriented religious colony, Preston Ranch was located north of Cloverdale, California on Oak Mountain. Life centered on the Christian teachings and medical practices of faith healer Madame Emily Preston, who was said to see through people with her "X-ray eye." She patented and then dispensed medicines through a thriving mail-order business. Most of her medicines were alcohol-based. Emily and her husband Hartwell held religious services at their home and advocated a direct personal relationship with God. The new faith was called the Religion of Inspiration.
Many skeptics accused Mrs. Preston of "quackery" and "occult spiritualism". Some claimed she was delusional. Attempts by doctors to have her prosecuted for the illegal trade of drugs failed. She was eventually stopped from dispensing her medicines by the passage of the Pure Food and Drug Act.
Emily Preston eventually won over many critics and became a respected figure in northern California. The settlement was successful and productive. When Preston died in 1909, the settlement lost its economic base and gradually faded away. Most of the Preston buildings, including the Preston Mansion, were destroyed in a fire in 1988.