San Simeon is a populated place on the Pacific coast of San Luis Obispo County, California, United States. Its position along State Route 1 is about halfway between Los Angeles and San Francisco, each of those cities being roughly 230 miles (370 km) away. A key feature of the area is Hearst Castle, a hilltop mansion built by William Randolph Hearst in the early 20th century that is now a tourist attraction. The area is also home to a large northern elephant seal rookery, known as the Piedras Blancas rookery, located 7 miles (11 km) north of San Simeon on Highway 1.
According to the United States Census Bureau, the census-designated place covers an area of 0.8 square miles (2.1 km2), all of it land. The original townsite of San Simeon is at San Simeon Bay, and was the important 19th-century shipping point with the successive wharves that were built. San Simeon Acres, about 4 mi south of the original townsite at the mouth of Pico Creek, and so about halfway between old San Simeon and Cambria, was established in the 1950s. Most of the development at San Simeon Acres was in the 1960s to the 1980s. Many motels and cafes serve visitors to Hearst Castle.
The 2010 United States Census reported that San Simeon had a population of 462. The population density was 579.9 people per square mile (223.9/km2). The racial makeup of San Simeon was 58.4% White, 0.9% African American, 1.1% Native American, 1.9% Asian, 0.4% Pacific Islander, 34.6% from other races, and 2.6% from two or more races. Hispanics or Latinos of any race were 55.8%.
Of the 197 households, 26.9% had children under the age of 18 living in them, 47.7% were married couples living together, 7.1% had a female householder with no husband present 6.6% had a male householder with no wife present, 6.1% were unmarried opposite-sex partnerships, and 2.5% were same-sex married couples or partnerships; 34.0% of the households were made up of individuals, and 15.2% had someone living alone who was 65 years of age or older. The average household size was 2.34. About 61.4% of all households were families; the average family size was 3.00.
The population was distributed as 22.9% under the age of 18, 6.7% aged 18 to 24, 24.2% aged 25 to 44, 28.1% aged 45 to 64, and 18.0% who were 65 years of age or older. The median age was 40.7 years. For every 100 females, there were 105.3 males. For every 100 females age 18 and over, there were 102.3 males.
The 301 housing units averaged 377.8 per square mile (145.9/km2), of which 44.2% were owner-occupied, and 55.8% were occupied by renters. The homeowner vacancy rate was 2.2%; the rental vacancy rate was 11.3%; 31.0% of the population lived in owner-occupied housing units and 68.8% lived in rental housing units.