Early History
There is no existing document that shows who or when the underground river was first discovered, but it is believed that the islands early inhabitants were the first to know of the existence, but their fear of spirits that they believe inhabit the caves prevented them from exploring the depts. The earliest mention one could hold of would be that of an Assistant Professor of Zoology at the University of Michigan who later became the Secretary of Interior at the first decade of American rule, Dean C. Worcester who wrote in 1887 while touring the island of Palawan “if accounts are to be believed, of a lake opening to the sea by a subterranean River”.