Fresnillo, city, central Zacatecas estado (state), north-central Mexico. It lies on an interior plateau more than 7,000 feet (2,100 metres) above sea level and northwest of Zacatecas city, the state capital. It was founded in 1554 and has been an important silver-mining centre since 1569. Limited quantities of gold, copper, lead, and zinc are also produced. Irrigation has increased grain and vegetable production in the area; the livestock industry dates from the colonial period. The city is accessible by highway and air and is near a major rail line. Pop. (2010) 120,944; (2020) 143,281.