By Peretz Partensky from San Francisco, USA (Thousand Island Lake Uploaded by russavia) [CC BY-SA 2.0 (], via Wikimedia Commons


Looking west from the outlet of Thousand Island Lake, Banner Peak looms in the distance creating a backdrop worthy of a postcard. The deep blue alpine water sparkles in the sun and is speckled with the tiny granite islands for which the lake is named. Brightly colored tents are scattered on the ridge overlooking the northern shore and hikers pass by on the nearby John Muir Trail.

From the Agnew Meadows Trailhead near Mammoth Lakes, I set out for a long day hike to Thousand Island Lake — the headwater of the Middle Fork of the San Joaquin River, a major watershed in California. Although the water has more of an impact on the sustainability of the environment and the people of the state, it’s more famously known for its image, which was famously captured by Ansel Adams. The lake has even appeared on the label of Sierra Nevada Brewing Company’s Summerfest, a seasonal lager beer.

In this region the Pacific Crest Trail (PCT), which travels 2,650 miles from the Mexico-California border north to the Washington-Canada border, is also known as the High Trail. The route traverses the San Joaquin Ridge and offers unobstructed views across the river valley to the Minarets and Ritter Range, a small mountain range within the Sierra Nevada that is comprised of the craggy Minaret peaks, Mount Ritter and Banner Peak. The range divides the drainages of the Middle and North Fork of the San Joaquin River. From my vantage point on the trail I can see a number of smaller creek drainages that flow into the San Joaquin River.

Read “Hiking the Headwaters: Finding Flow in the San Joaquin River High Country” online at

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