There are no cultural records of historical eruptions. However, weak steaming is currently present in some of the heavily eroded vents on the North Western side of the summit. The ancient eruptions were said to have caused the formation of a Lava Dome on the Western Slopes of the mountain known as White Rock which makes a nice tourist destination and is usually a field trip destination for students of Pampanga State Agricultural University. The Arayat amphitheatre is said to have been caused by the summit's collapse on the western side but a much deeper crater is present on the eastern side, it was said that the mountain was once a volcanic island, until eruptions covered the surrounding area with soil, eruptions were said to be the possible cause of a theorized re-route of Pampanga River which is said to have once passed on the western side rather than eastern side where it currently moves.