The Valley of the 10,000 Smokes was created on June 6, 1912 by the eruption of the Mt. Katmai through Novarupta. This valley covers about 56 square miles and it is now part of the Katmai National Park and Preserve. It was recorded to be one of the most gigantic eruptions in recorded history which blasted more than 7 cubic miles of earth in only 60 hours. Kodiak Island was buried under 1 foot of ash and fumes produced acid rain 370 miles away. The high altitude haze became visible a few days later in Washington D.C.

The valley where the ash was blasted was left with tens of thousands of jets of steam and gas ranging up to 1,200 degrees F bursting from vents in the earth up to 150 ft high. More than 40 of the valleys 56 square miles were covered in ash up to 700 ft. The summit of Mt. Katmai had collapsed leaving a crater with a measurement of two miles miles by three miles and a lake 3700 ft below the rim. A new volcano, the Novarupta, had risen in the valley southwest of Katmai. All plants and animal life had been destroyed. More than 60 years later there were less than twelve fumaroles, but the region had been so moon-like that in the 1960s it was used in training U.S. astronauts for moon landings.

Geologists have been puzzled about these series of events for a long time. The most recent theories have a logical explanation based on map measures of the ash level. These theories suggest that the activity came from the Novarupta. It first exploded with lava that flowed across the valley floor and from nearby fissures. Following these first blasts a large column of molten material that was beneath Mt. Katmai erupted beneath Novarupta. Almost as quickly as the two lavas joined they erupted upward.

It is thought that the top of Mt. Katmai was destroyed soon after the lava flow from under began. There is evidence of volcanic activity in the crater itself and the fact that the lake remains unfrozen in the winter.

Plant life was very slow to return to the buried valley. Moss and algae first appeared near the fumaroles, but some higher plants have begin to grow on the valley floor. The valley is unable to keep animal life, but moose and bear may cross the valley occasionally. In recent years it has become a popular tourist attraction, reached by bus and foot from the National Park Service Lodge at Brooks Camp.