Leaving Redwood country we drove inland following the Rogue River into the mountains of Southern Oregon where our next stop was Crater Lake National Park. Arriving there in the late afternoon we stopped off at the visitor centre to find out all we could.
Crater Lake is what remains of a volcano called Mount Mazama which erupted about 7,700 years ago. Over the preceding half a million years the mountain had been slowly growing via a series of eruptions and reached a height of circa 14,500 feet when it really started blowing. Accounts from the local Native American tribe recorded at the time show that over the course of about a week it spewed rocks, ash and other debris covering an area of 10,000 square miles to an average depth of 2 feet.
Once this had finished the was a brief period of quiet, which was broken one morning by a series of immense explosions which lasted a few hours and turned out to be the cone of the mountain collapsing in on itself. This is left a huge circular crater 5 miles by 6 miles across and an average of 3,500 feet deep, additionally the scale of the eruption and subsequent collapse had reduced the mountain’s height by half to an average of 7,500 feet – it had quite literally blown its top off. That’s a lot of bang for your buck…
With the crater now formed, the mountain was quiet for the next 300 years or so before a series of new eruptions occurred, some of which were large enough to create new peaks within the crater – the largest being Wizard Peak which you can see in the picture below, the classic volcano shape…
Over the course of the of the next 3000 years it began to fill with water from the annual rainfall and snowmelt, slowly filling it to the level it has remained ever since. If you think that sounds unlikely, I should add that Crater Lake receives 44ft of snow each year, making it the snowiest place in the US. The average depth of the lake is 1,148 feet and its lowest point of 1,949 feet makes it the deepest lake in North America. The water level remains pretty much constant due to natural evaporation and seepage through the porous rocks at circa 5,000ft and despite the intense winter cold its 5 trillion gallons of water which circulates up and down ensures that it never freezes over.
The snow usually starts to fall in mid-September and the last falls are during May (in fact the last snowfall was just 2 days before we arrived) and it’s often still lying on the ground well into July, which is why we found ourselves dwarfed by the huge drifts even with a daytime temperature of 12 degrees.
It’s an extraordinary place of ethereal beauty, with the water acting as a mirror for the crater rim, cliff faces and sky and it’s so clear is that the naked eye can see objects 140ft below the surface. A true place of wonder and awe.