The andesitic Banahaw volcano complex is composed of several mountains with Mount Banahaw, the largest with a maximum elevation of above mean sea level. The summit is topped by a and deep crater that is breached on the southern rim believed to have been caused by the 1730 eruption. Prior to 1730, a lake occupied the summit crater of Mount Banahaw. The resulting flood destroyed the town of Sariaya, Quezon located below the mountain.