Located at barangay Liwayway, Diffun, Quirino with an area of 25 hectares. Its special natural features are its glaring limestone formation, wide array of secondary forest of small trees, 15 scattered caves series with enigmatic underground river and presence of bat caves in the area. The area is known of its natural monuments and wildlife habitat. A twenty (20) minute ride from the town proper passing through by an all weather road. Its management is being claimed by LGU-Diffun. One of the caves was used before by the Union Esperitista for their religious worship and service. Eco-trails were also introduced by local folks. Yearly the caves are often visited by local tourists with its peak especially every summer season. Some caves were exploited by bat manure permittees and became a hunting place for wild birds and animals rampant collection of swift/nido nest.