The trail climbs up the ridge above the Thumbnail until dipping a short distance on the ridge's south side. It then ascends back to the ridgeline, moves through some boulders to the north side, and then switches back to the south through a notch with a short slippery slope beneath. Contour around the ridgeline crest again moving westward, and generally follow the ridgeline, occasionally passing obstacles on the south. A final venture on the south flank of the ridge and ascent back to the weather station/radio facility takes you to the top of East End, the highest point in the McDowell Mountains. Surveyors have placed multiple USGS markers on the summit rocks. On the accompanying route map, this area is indicated as WP 17. [links]