The San Pablo volcanic field, (also known as the Laguna volcanic field ) lies at the southern end of Laguna de Bay, the largest lake on Luzon Island. The volcanic field contains dozens of scoria cones and maars. Three generations of maars are present, with the oldest being sediment-filled and the youngest containing deep lakes. Many of the maars are aligned along a NE-SW trend. Local legends suggest that the youngest maar, 1.2-km-wide Sampaloc Lake, was formed about 500-700 years ago. The high point of the volcanic field is the eroded Maquiling (Makiling) andesitic-to-rhyolitic stratovolcano, which has a deep crater whose floor is 480 m below its north rim. Maquiling has several parasitic cones, maars, and numerous thermal areas at its northern base. A geothermal project is located on the south flank of Maquiling.