Rainbow Lake to Nobles Trail starts in the thin fir forest at a well marked trail junction on the east side of Lower Twin Lake in the Lassen Volcanic National Park backcountry. From here, among the firs, the trail heads northeast over a small rise covered with lupines. Descending gradually, Rainbow Lake comes into view, and is reached at the 0.6 mile mark. The trail then runs along the northern edge of Rainbow Lake for the next quarter mile.
At the northeast corner of Rainbow Lake, a trail junction with Rainbow Lake Trail
is reached. Stay left here to continue on Rainbow Lake to Nobles Trail. The trees start to become sparser as the trail makes a short gradual final climb before descending gently to its end. Descending, the trail goes through a regenerating burn zone and views of the surrounding mountains emerge. Forested Prospect Peak
, 8.338 ft., is seen to the north. Further on the ridge of peaks to the east come into view.
Healthy forest then returns for a short stretch before the terrain gives way to barren volcanic ash for about the last half mile. Cinder Cone
comes into view here. Traveling over the volcanic ash, trees become sparser and finally there are only occasional lone trees dotting the volcanic ash flats.
Rainbow Lake to Nobles Trail ends after 3.1 miles, where it joins Butte Lake to Snag Lake Trail (West)
that comes in from the east. This is just shy of Nobles Emigrant Trail (East)
that comes in from the west and various trails to Cinder Cone
Thin fir forest. Wild flowers especially fields of lupines west of Rainbow Lake. Deer. A variety of birds in the western stretch - if you're lucky you'll see Western tanagers.