Hillary Rodham gazed out the window of the beat-up ’68 Buick rolling down Interstate 81, and saw spruce trees, the Blue Ridge Mountains and the life she’d left behind.

Ms. Rodham, then a 26-year-old lawyer, had just finished working on the Watergate committee and wanted to be with her boyfriend, Bill Clinton, who was teaching law in Arkansas.

Her landlord, Sara Ehrman, who worried her bright young tenant was throwing away her future, offered to drive her down from Washington, and over the course of two days and 1,193 miles in August 1974, Mrs. Ehrman tried to talk Ms. Rodham out of her plan.