The Lawu, or Mount Lawu is a massive compound stratovolcano straddling the border between Ngawi, East Java and Central Java, Indonesia. The north side is deeply eroded and the eastern side contains parasitic crater lakes and parasitic cones. A fumarolic area is located on the south flank at 2,550 m. The only reported activity of Lawu took place in 1885 when rumblings and light volcanic ash falls were reported. The recent study provided insights into geothermal heat flow suggesting that Mt. Lawu is still active today.