For one of the most extreme places in Oregon, we turn northeast to Crater Lake.

For one of the most extreme places in Oregon, we turn northeast to Crater Lake.

For starters, the lake, as nearly everyone in the Northwest old enough to drive to it knows, is the deepest in the nation at 1,943 feet. That makes it at least the seventh deepest in the world.

But that is just the beginning of unique characteristics that make the internationally known lake in Oregon's only national park stand out, drawing half a million visitors a year, albeit largely during the summer.

Consider the water, which is one of the clearest on the planet. Using a special reflector known as a Secchi disk, scientists recorded a clarity reading of 142 feet on June 25, 1997, making it the clearest in the nation.

The extreme blue color of the water comes from the fact that blue is the last color to be absorbed by deep water, scientists explain.

It is also the only lake in the nation to have a mountain hemlock floating upright in it for more than 100 years. Driven by the wind, the tree is known as the "Old Man" of Crater Lake.

With a surface that is about 6,150 feet above sea level, the lake is fed almost entirely by snowfall, which averages an extreme 530 inches a year. The winter of 1932-33 set a record of 879 inches of snow for the park, which is one of the snowiest places in the Pacific Northwest.

And 1950 brought an avalanche of 903 inches, establishing a state snowfall record for a calendar year. The National Park Service began officially keeping weather records at the park headquarters in 1926.

Since there is no outlet from the lake, evaporation and seepage keep the water level from making drastic fluctuations, even following a winter of heavy snow. The highway around the lake rim, which rises to about 7,000 feet, is often closed by snow until June.

Despite its high elevation, the lake surface rarely freezes. Not since the winter of 1949 when the entire surface was frozen for more than three months has there been a significant lake freeze, according to park records.

Yet it was not ice from Crater Lake National Park that led scientists to accurately determine when Mount Mazama blew its top, observes Ed Danehy, a retired geologist living in Medford. He notes that scientists studying ash from Mazama's eruption found in ice cores from the Greenland ice sheet were able to determine the caldera was created in 5,677 B.C., making it just shy of 7,700 years old.

In addition, geologists have estimated that Mazama stood about 12,000 feet above sea level before the eruption, making what would have been the tallest mountain in Oregon, another extreme. The cataclysm that sent ash deposits as far as Greenland was nearly 50 times that of Mount St. Helens when it erupted on May 18, 1980, according to the U.S. Geological Survey office in Menlo Park, Calif.

Finally, both archaeological evidence and oral tradition suggest Indians witnessed the explosive event and held the area sacred for thousands of years.

Archaeologists have found sandals and other artifacts buried under layers of Mount Mazama ash and pumice from the eruption. Although they say the mountain wasn't likely a permanent home to people, it was a place for vision quests and prayer.

Stories told by the Klamath Indians, descendants of the Makalak people who once lived in the area immediately southeast of the national park, tell how the lake was formed during a battle between Llao, god of the underworld, and Skell, god of the overworld. Llao became angry after he was spurned by an Indian chief's daughter, and in his rage rushed up through the top of the mountain and began hurling rock and fire down upon the Indian people.

The mighty Skell took pity on the people and forced Llao to retreat back to the underworld, leaving behind one of the deepest calderas in the world.

Reach reporter Paul Fattig at 541-776-4496 or email him at