The largest eruption of the 20th century occurred in 1912 in Alaska, from June 6 to June 8, to form Novarupta. It was so powerful that it drained magma from under another volcano, Mount Katmai, six miles east, causing the summit of Katmai to collapse to form a caldera half a mile deep. For 60 hours the eruption sent tall dark columns of tephra and gas high into the atmosphere. By the time the eruption ended the surrounding land was devastated and about 30 cubic kilometers of ejecta blanketed the entire region. It was thirty times more than the 1980 eruption of Mount St. Helens and three times more than the 1991 eruption of Mount Pinatubo, the second largest in the 20th Century. Volcanic lightning and thunder added to the terror on Kodiak Island during the first day of the eruption. Despite the fact that the eruption was comparable to that of the far more famous eruption of Krakatau in Indonesia in 1883 and so near the continental United States, it was hardly known at the time because the area was so remote from English-speaking people; no one died except a woman already stricken with tuberculosis aboard a ship docked at Kodiak, where more than one foot of ash fell and noxious gases persisted for days. In place of Mount Katmai summit today is a magnificent crater lake surrounded by 300-foot walls that echo the thunder of glaciers that now calve into lake.