Butuan (also called as Kingdom of Butuan) was a precolonial Philippine polity centered on the northern Mindanao island in the modern city of Butuan in what is now the southern Philippines. It was known for its mining of gold, its gold products and its extensive trade network across the Nusantara area. The kingdom had trading relationships with the ancient civilizations of Japan, China, India, Indonesia, Persia, Cambodia and areas now comprised in Thailand.The balangay (large outrigger boats) that have been found along the east and west banks of the Libertad river (old Agusan River) have revealed much about Butuan's history. As a result, Butuan is considered to have been a major trading port in the Caraga region during the pre-colonial era.