San Marcos is a town and a municipality in the Carazo Department of Nicaragua. It is located 45 km south of the capital Managua. The mu…San Marcos is a town and a municipality in the Carazo Department of Nicaragua. It is located 45 km south of the capital Managua. The municipality has a population of 33,303. San Marcos' climate enables the production of coffee and a large variety of tropical flowers and fruits.