1) Green Lakes Trailhead, Green Lakes - This trailhead is along the Cascade Lakes Highway east of Mt Bachelor. During winter this road is only cleared as far as the ski area, spring opening depends on the snowpack but is usually around Memorial Day weekend. There is a popular and well maintained trail to Green Lakes where there is camping. This approach is often used for the NW Ridge and from Green Lakes it is possible to climb South Sister as well.
2) Broken Top Trailhead - To reach this higher elevation trailhead (approx 7000') turn off Cascade Lakes Highway at the well signed and paved Todd Lake road. If the gate after a mile or so is open the rough road can be followed for several miles until a left turn which is marked and signed for the trailhead is reached. The road is often gated at Todd Lake until mid or late summer when the road surface dries in order to prevent rutting and other environmental damages. This is the most common approach for any routes in the crater such as South Face Gully, Eleven O'Clock Couloir, or Nine O'Clock Couloir. It can also be used for the Northwest Ridge or for north side routes. In winter this is the only feasible approach, and even so it is necessary to ski in from the Mt Bachelor parking lot or Dutchman Flats snowpark.
3) Three Creeks Lake - This road and trailhead could conceivably be used for routes on the north side of the mountain. This road is also not open to its end in winter although snowmobiles are permitted for travel on the unplowed section. This paved road begins in the town of Sisters and heads south.