The coastline, including Big Sur, State Route 1, and the 17 Mile Drive on the Monterey Peninsula has made the county world famous. The city of Monterey was the capital of California under Spanish and Mexican rule. The economy is primarily based upon tourism in the coastal regions, and agriculture in the Salinas River valley. Most of the county's people live near the northern coast and Salinas valley, while the southern coast and inland mountain regions are almost devoid of human habitation.
As of the census of 2000, there were 401,762 people, 121,236 households, and 87,896 families residing in the county. The population density was 121 people per square mile (47/km²). There were 131,708 housing units at an average density of 40 per square mile (15/km²). The racial makeup of the county was 55.92% White, 3.75% Black or African American, 1.05% Native American, 6.03% Asian, 0.45% Pacific Islander, 27.82% from other races, and 4.98% from two or more races. 46.79% of the population were Hispanic or Latino of any race. 6.3% were of German and 5.4% English ancestry according to Census 2000. 52.9% spoke English, 39.6% Spanish and 1.6% Tagalog as their first language.
There were 121,236 households out of which 39.1% had children under the age of 18 living with them, 56.0% were married couples living together, 11.6% had a female householder with no husband present, and 27.5% were non-families. 21.2% of all households were made up of individuals and 8.2% had someone living alone who was 65 years of age or older. The average household size was 3.14 and the average family size was 3.65.
In the county the population was spread out with 28.4% under the age of 18, 10.9% from 18 to 24, 31.4% from 25 to 44, 19.3% from 45 to 64, and 10.0% who were 65 years of age or older. The median age was 32 years. For every 100 female residents there were 107.3 male residents. For every 100 female residents age 18 and over, there were 107.7 male residents.
The median income for a household in the county was $48,305, and the median income for a family was $51,169. Men had a median income of $38,444 versus $30,036 for women. The per capita income for the county was $20,165. About 9.7% of families and 13.5% of the population were below the poverty line, including 17.4% of those under age 18 and 6.8% of those age 65 or over.
Monterey County is served by Amtrak trains and Greyhound Lines buses. Monterey-Salinas Transit provides transit service throughout most of Monterey County, with buses to Big Sur and King City as well as in Monterey, Salinas and Carmel. MST also runs service to San Jose.