San Mateo County
San Mateo County is on the Peninsula in the San Francisco Bay Area in California. San Mateo County is all of the peninsula from San Francisco extending south until nearly the southern end of the bay, South Bay.
Be careful to check for ticks after hiking in fields in the bay area. There is a high rate of lyme disease transmission in the Bay Area. If a bulls' eye rash develops at the tick bite site, immediately seek medical help and treatment with antibiotics.