At the end of the improved part of the trail, we reach Landscape Arch (fig. 53), claimed by the Park Service to be the longest known natural arch in the world. According to Ouellette (1958) it is 291 feet long and 118 feet high, but Professor Stevens’ measurements indicate it to be 287 feet long and 106 feet high. At its thinnest point on the right, the span is only 11 feet wide and 11 feet thick. In 1958 three young men made what was claimed to be the second known ascent of Landscape Arch, using ropes and other climbing gear, after which they walked across (Ouellette, 1958). This crossing was made with the permission of a park ranger, but such permission is no longer given, for the safety of both the arch and of would-be climbers. Wall Arch is about a quarter of a mile beyond the end of the improved part of the trail, and another three-fourths mile brings us to Navajo Arch (fig. 54) and Partition Arch (fig. 55). A distant view of Partition Arch may be had just before reaching Landscape Arch. Part of the remaining trail to Double O Arch (fig. 56) is on the top of a low sandstone fin, in part between somewhat higher fins and in part above lower slots. [Illustration: LANDSCAPE ARCH, viewed southwestward from near end of improved part of Devils Garden trail. Note that ground beneath arch is covered by slope wash and near the middle with what appears to be a small landslide. Slick Rock Member here is more nearly buff than salmon colored, because of a smaller content of iron oxide. Fresh breaks and angular blocks of stone at right abutment indicate relatively recent rock falls. See text for size. (Fig. 53)] [Illustration: NAVAJO ARCH, viewed northeastward from a branch of Devils Garden trail. One of few arches having a flat soil-covered floor. Opening is 40½ feet wide. Photograph by National Park Service. (Fig. 54)] Beautiful Double O Arch (fig. 56) is at the end of the Devils Garden trail about 2½ miles northwest of the trailhead. About half a mile northwest of the trail’s end is a prominent landmark called Dark Angel (fig. 57), which is visible in figure 12 and from the unimproved road in Salt Valley. [Illustration: PARTITION ARCH, viewed southwestward from near Devils Garden trail. Arch frames part of south wall of Salt Valley and, on skyline, mesas south of Moab Valley. Opening is 27½ feet wide and 26 feet high. A smaller opening to the right measures 8½ feet wide and 8 feet high. Photograph by Dawn E. Reed. (Fig. 55)] [Illustration: DOUBLE O ARCH, viewed about north from northwest end of Devils Garden trail. Large opening is 71 feet wide and 45 feet high; small one at lower left is 21 feet wide and 11 feet high. Span of large opening is 11 feet wide and 6 feet thick. Arch frames a part of the Book Cliffs about 14 miles to the north. Photograph by Hildegard Hamilton, Flagstaff, Ariz. (Fig. 56)]