Marcos is a cdp located in San Diego County, in the state of California (CA), United States. Nestled in the Pacific division of the West region, it covers an area of 1.8 square miles (5.0 km²) and sits at an elevation of 520 ft. With a population of approximately 4,138 residents, Marcos offers a peaceful, rural atmosphere.
The town's population is composed of about 43.52% males and 56.48% females, and it has a population density of 286.19 people per square mile (882.70/km²). Marcos lies at a latitude of 33.12 and a longitude of -117.21, operating in the UTC-8.
Locals reflect a blend of American ancestry, with roots primarily in United States (6.8%), followed by English (21%), German (17.8%), and Scotch-Irish (0%) heritage. The town is identified by the ZIP code 92069.