The original trail system of 1891 had been extended to include a trail up Little Yosemite Valley to Merced Lake, Vogelsang Pass and thence down Rafferty Creek to Tuolumne Meadows, a route that is familiar to all High Sierra hikers of the present day. The Isberg Pass trail to the east boundary of the park had been marked and Fernandez Pass, farther to the south, had also been rendered accessible by a trail that branched from the original trail along the southern boundary. The present trail from Tuolumne Meadows up the Lyell Fork of the Tuolumne to Donohue Pass also dates from this period. From Tuolumne Meadows a trail also reached out into the remote northern portion of the park to the vicinity of Glen Aulin, thence up Alkali Creek to Cold, Virginia, and Matterhorn canyons. From the latter point this route continued westward to Smedberg Lake, down Rogers Canyon, eventually passing through Pleasant Valley and over Rancheria Mountain to Hetch Hetchy Valley. The Ten Lakes area was accessible by means of a trail originating on the Tioga Road near White Wolf, and from Hetch Hetchy Valley trails radiated to Tiltill Mountain, Miguel Meadow, Lake Eleanor, Vernon Lake, and up Moraine Ridge to a point near what is today known as the “Golden Stairs,” overlooking the lower portion of Jack Main Canyon. A route approximating the present Forsythe trail from Little Yosemite around the southern shoulder of Clouds Rest to Tenaya Lake had been established, and from Tenaya Lake the point now known as Glen Aulin could be reached by the McGee Lake trail. The routes taken by these early trails were essentially the same as those of the present day and points mentioned will be familiar to all who enjoy roaming about the Yosemite back country. When the National Park Service came into existence in 1916, the broad design of the trail system was essentially as it is at present. The more important trails constructed during the last years of Army administration and in the first years of the National Park Service regime include the Tenaya zigzags built in 1911; the Glen Aulin-Pate Valley route, 1917-1925; the Babcock Lake Trail; the Yosemite Creek-Ten Lakes Trail; the Ledge Trail to Glacier Point, 1918; the Harden Lake-Pate Valley Trail, 1919; Pate Valley-Pleasant Valley Trail, 1920; and the Ottoway Lakes-Washburn Lake Trail in 1941. Gabriel Sovulewski, who for more than thirty years supervised the construction of Yosemite trails, once outlined for me the amazing story of the evolution of the trail system from Indian routes and sheep trails (Sovulewski, 1928, pp. 25-28). Mr. Sovulewski stated, “Most of these improvements were made on my suggestion, and sometimes at my insistence, yet it is necessary to bear in mind that the credit is not all due to me, even though I did work hard. I share the credit with all superintendents under whom I have served. They gave me freedom to do the work which I have enjoyed immensely.”