After crossing the plateau, Zosia and I passed through a short stretch of forest before grinding up a big open slope.  The trail is steeper here and is also heavily braided, but with good visibility, we had no trouble staying on track.  The last part of this slope just below a tarn has perhaps the sketchiest section of trail on the entire mountain.  There was a lot of loose and slippery rubble here, and some care and focus were required to maintain good footing.  The aforementioned tarn was a good place for us to stop and catch our breaths before the final lengthy push up a lateral moraine and then a steep slope of red pumice.  I felt weary and slowed considerably here, but otherwise, we had no other issues reaching the crater rim of South Sister.  The actual summit is on the far side of the crater, and like the majority of other hikers, we circled the rim in a counterclockwise direction on a well-beaten path before finishing the ascent with a short and easy scramble.  With a steady stream of other hikers arriving and congregating at the summit, we decided to move further around the rim to find a quieter spot for an extended break.

Zosia and I spent a good hour relaxing on the crater rim before reluctantly resuming our hike.  We had to do a little bit of scrambling to get down a short dip before climbing back up to complete our circumnavigation of the crater.  Once we returned to the spot where we first gained the rim, we simply retraced our steps down the mountain.  Some of the red pumice high up worked well for a bit of scree surfing, but otherwise, it was mostly a long and relentlessly knee-jarring descent.  We had a bit of a reprieve from the constant downhill pull when we re-crossed the treeless plateau, but the final section down the drainage, while not so steep, felt interminable.  When we reached Tyee Creek, we took another extended break here to refresh ourselves in the icy waters before walking the final short distance back to the trailhead.  Somewhat disappointingly, there were no conservation officers there checking for our hard-won permits.

	Zosia begins hiking at 3:52 AM PDT.
	Just before sunrise, Zosia passes Moraine Lake.  Behind her are Devils Hill and Mount Bachelor.
	Hiking across this treeless plateau, Zosia gets her first clear look at South Sister.
	The first rays of sunshine can be seen near the top of the mountain as Zosia steadily grinds uphill.
	Here is a look back down at the plateau (left of centre) that was crossed earlier with Mount Bachelor on the left horizon.
	This steep section just ahead of Zosia is perhaps the sketchiest part of the entire trail with lots of loose and slippery rubble.
	Zosia pauses for a break near an unnamed tarn below Lewis Glacier.
	This golden-mantled ground squirrel is probably used to seeing hordes of intruders on a daily basis. Photo courtesy of Zosia Zgolak
	The trail goes up a lateral moraine beside Lewis Glacier.
	Zosia begins climbing the final steep section of red pumice.  Note the long line of hikers ahead of her.

Here is a look back down south from the top of Lewis Glacier.

 

	Zosia hikes along the crater rim with the summit just ahead.
	The northeast side of the mountain is covered by Prouty Glacier.
	Zosia sits atop the summit of South Sister (3157 metres).

The view to the north is dominated by Middle Sister and North Sister.  Also visible behind North Sister are Mount Jefferson and Mount Hood.

 

Inside the crater of South Sister is the eye-catching Teardrop Pool.

 

	Here is a closer look at Teardrop Pool.
	Sonny carefully scrambles down a dip in the crater rim.  Note the hiker climbing up the other side. Photo courtesy of Zosia Zgolak
	Here is one last look at the summit of South Sister directly above Teardrop Pool.
	On her way down, Zosia stops to admire the view of Broken Top (far left) and Mount Bachelor (far right).  The smaller bump to the left of Mount Bachelor is Tumalo Mountain, and behind it on the distant horizon is Paulina Peak.
	Amazingly, grasshoppers appear to thrive on the upper mountain where there is little vegetation. Photo courtesy of Zosia Zgolak
	Zosia re-crosses the treeless plateau on descent.
	Zosia gets to see the mossy forest which she missed in the dark at the start of the trip.
	This tunnel allows hikers to avoid crossing the dangerous highway on the way to South Sister. Photo courtesy of Zosia Zgolak
	Here is a final look at South Sister from Elk Lake.
	Total Distance:  20.8 kilometres Round-Trip Time:  11 hours 30 minutes Cumulative Elevation Gain:  1486 metres GPX Data