Pilan Rock Formation

The Pilan Rock Formation is a geologically significant site along the Pilan River, renowned for its striking columnar basaltic andesite structures. These vertical, hexagonal rock columns were formed when thick lava flows cooled slowly and contracted, creating fractures that developed into the distinctive geometric patterns seen today.

Beyond its visual appeal, the formation offers a tangible demonstration of volcanic cooling and erosion processes that shaped the foothills of Mount Apo. Over time, river action has exposed and sculpted these basaltic andesite columns, making the site both a natural classroom for understanding volcanic geology and a scenic landmark for visitors. The Pilan Rock Formation stands as a testament to the immense geological forces that built and continue to shape the Philippines’ highest peak.