In the seven thousand years since Mount Mazama’s upper cone collapsed into a steep crater during a tremendous eruption, abundant snowmelt has accumulated to form the deepest lake in the country, an impossibly large and beautiful circle of pure, intense blue. I arrived in a snowstorm that obscured the lake from view. Drawn to the pristine blanket of snow on the trees, I started hiking along the rim in snowshoes, hopeful that the storm would weaken. Moments before dark, to my elation, the clouds lifted to reveal the entire extent of the lake as the last light colored the sky.