On the second day, embark on a trekking adventure to explore the natural beauty of Biak-na-Bato National Park. Start with the Madlum River, where you can enjoy a refreshing swim in its crystal-clear waters. Continue your trek to the Madlum Cave, known for its unique rock formations and underground river. After exploring the cave, hike up to the summit of Mt. Manalmon for breathtaking panoramic views of the surrounding landscape. Take a leisurely nature walk through the park's lush forests, keeping an eye out for the diverse flora and fauna that call this place home.