San Marcos is a barangay of the philippine municipality Bunawan in the province Agusan Del Sur
which is part of the Mindanao group
San Marcos is one of the barangays which are in the outlying area of Municipality Bunawan.
The municipality Bunawan with a population of about 35,757 and its 10 barangays belong to the partly urban areas in the Philippines. While some of the barangays developed modern urban structures, some others, especially those which are seated in the outlying areas, remained rural. By the end of 2007 San Marcos had 1,235 residents.
Other barangays of Bunawan are:
Bunawan Brook, Consuelo, Imelda, Libertad, Mambalili, Nueva Era, Poblacion, San Andres, San Teodoro