the province annually celebrates its naliyagan festival, a celebration of the foundation anniversary of agusan del sur which is a week-long socio-cultural and arts exposition of indigenous tribes in the entire agusan valley and displaying their skills and gracefulness in dancing as part of their ritual activities. it is being held in the naliyagan plaza at the agusan del sur capitol grounds in the municipality of prosperidad. "naliyagan" is a manobo word which means "the chosen one" or "the most loved one".