Waldo Lake is a natural alpine lake in the Cascade Mountains of the U.S. state of Oregon. It is the second largest natural non-alkali lake in Oregon with just under 10 square miles of water surface and a maximum depth of 420 feet. The lake is named after Oregon politician, judge, and conservationist John B. Waldo.
Location: Cascade Mountains, Lane County, Oregon, US
Primary outflows: North Fork Middle Fork Willamette River