Valle de Santiago is a municipio (municipality) in the Mexican state of Guanajuato, and also the name of its largest township and cabecera municipal (municipal seat). The municipality is located in the southern portion of the state in the Bajío region of central Mexico, and has an area of some 820.1 square kilometres (316.6 sq mi). The city of Valle de Santiago lies at an elevation of 1,744 metres (5,722 ft) in the east-central part of the municipality, approximately 90 kilometres (56 mi) south of the state capital, Guanajuato.