Northeast of Christmas Valley, the natural sand dunes cover 11,000 acres/45 km2. They consist of mostly pumice and ash from the explosive eruption of Mt. Mazama that formed Crater Lake.
The easy way to get there: Take Hwy-97 south from Bend, turn on Hwy-31 towards Fort Rock and Summer Lake & Lakeview. Head east on County Road 5-10, pass by Fort Rock (or stop and check it out first), then follow it until the road changes (on a corner) to County Hwy 5-14. That will take you to Christmas Valley.
After leaving town, you can turn north on Crack in the Ground Road to see an unusual site. More about that later…
Continue down County Hwy 5-14, for a couple minutes, and turn north (left) onto County Hwy 5-14D (Fossil Lake Road). At the end of the road, turn right at the intersection. Continue down the road until you see the signage and the dunes.
Location via Google Maps.