These two uncrowded hikes on the south side of Crater Lake reveal the difference between a crater and a caldera. The 0.2-mile Sun Notch Trail climbs to a spectacular Crater Lake viewpoint above Phantom Ship’s craggy little island. But the astonishingly blue, 6-mile-wide lake you see here is not in a crater at all—it fills a caldera, a giant pit created by a mountain’s collapse. To see a true volcanic crater, take the nearby 3.2-mile path to Crater Peak, a cinder cone with a wildflower meadow in a cute little summit bowl. Pets are not allowed on either trail.

Start at the . . .

Much of Crater Lake’s geologic story is exposed at Sun Notch’s viewpoint. When eruptions started building Mt. Mazama 400,000 years ago, they began near here. Phantom Ship is a fragment of the volcanic plug from those early eruptions. As Mt. Mazama grew to an estimated height of 12,000 feet, the volcanic vents moved farther north, finally pouring out a thick dacite flow to create Llao Rock, the largest cliff visible across the lake. By then, glaciers were scouring deep U-shaped valleys into the mountain’s flanks. Sun Notch is a remnant of one of the largest of these glacial troughs, amputated when the mountain exploded 7700 years ago.

If you’d like to see a genuine crater after visiting Sun Notch, drive . . .

This chapter is an excerpt from 100 Hikes: Southern Oregon