Monterey County is located on the Pacific coast of California, with its northwestern section forming the southern half of Monterey Bay. The northern half of the bay is in Santa Cruz County. As of 2010, the population was 415,057. The county seat and largest city is Salinas.

The Monterey County 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.