Halema'uma'u Crater is the site of the most eruptions at the summit of Kilauea Volcano. Between 1905 and 1924, a period of about 20 years, a dazzling lake of molten lava circulated within its walls. Then, in 1924, the lake drained away, allowing ground water to penetrate deep inside the volcano. Enormous steam explosions resulted, showering the landscape with rocky debris, still visible around the rim today.During the 1924 steam blasts, Halema'uma'u collapsed, forming a gaping pit 1600 meters wide and 410 meters deep. Since then, 17 eruptions and 4 collapses have occured in the crater. The net effect has been a slight increase in the craters diameter and a decrease in its depth (from 410 meters to its present-day 85 meters).