There are 1 US Post Offices in Alpine County serving a total of 957 residents equating to 957 residents per post office. It's estimated that approximately 1,527 packages are handled across the 1 county post offices annually. Alpine County, officially the County of Alpine, is a county located in the U.S. state of California. As of the 2010 census, the population was 1,175. making it the least populous county in California. The county seat is the Census Designated Place of Markleeville. There are no incorporated cities in the county. Alpine County is located in the Sierra Nevada, between Lake Tahoe and Yosemite National Park."