According to the USGS map, the name "Jones Mountain" applies to not only the 13er summit, (13,218) but also applies to the ranked 12er at the north end of the summit ridge (12,995). Hence, our route description includes hiking to the 12er summit as well as the 13er summit.
The trail for Ptarmigan Lake crosses Middle Cottonwood Creek on a bridge and then heads ESE for about a half mile, climbing up through forest before it swings south, staying well above Ptarmigan Creek on its west bank. About a mile and a half up, at perhaps 11,280 feet elevation, the trail comes to a fairly open area not far from the creek and the other CR346 that is blocked by locked gate down at Middle Cottonwood Creek joins in. There’s a bunch of cut logs there and some good camping for those who may want to backpack into this area.
Continue on up the well-defined trail for another 1.5 miles until just before a small tarn marked on the USGS map at just below 11,800 ft. This is on the edge of the forest and there is a good view of North Jones Mountain (12,995) to the west. It made some sense to us to climb such a high 12er. After all – some day it could be re-measured and found to be a very low 13er, so we deiced to include it in our day hike. So we turned west off the trail and began ascending through open forest and up a steep grassy slope to a bench area at 12,100 feet on the east flank of the North Jones. The bench has open grassy areas and clumps of low evergreens. It also affords an outstanding view of Mt. Yale, towering far to the north. From this bench, ascend directly up the east face of the peak on mostly tundra, embedded rocks and small rubble to the summit. It took us only 26 minutes to gain that last 900 feet – a remarkable pace for a couple of aging peakbaggers.
From North Jones head south along the broad, open, tundra-covered ridge toward Jones. The mile and a half descent and then climb back up took us about an hour. Most of the ridge is tundra covered with some rubble on the steeper gain toward the Jones Mtn. summit. Abundant, earlier-season buttercups and blue flowers may accompany your stroll. There are also some nice clumps of Old-Man-On-the-Mountain to pause and photograph. The summit 13,218 summit of Jones Mountain is a large, broad summit area of tundra and chiprock scree. Pause for a lengthy break and some lunch and an opportunity to survey the surrounding countryside.
After your break, you can descend to the saddle east of Jones and above and south of Ptarmigan Lake. From a vantage point above the lake, you may see numerous day-hikers arriving at the lake. For us, it was a little early in the season for abundant wildflowers, but the grassy, tundra-covered slopes would soon bear quite a display. Having carefully studied the distant Gladstone Ridge from the summit of Jones, we had decided to leave that summit for another day. Weather had some bearing on our decision. It certainly did not appear that this would be a climb-forever type of day, it having already become fairly cloudy and threatening on the summit of Jones. Continuing to Gladstone Ridge will add 2.7 miles one-way or 5.4 miles round-trip.
As you approach the saddle east of Jones, and south of Ptarmigan Lake, pick up the Ptarmigan trail and hike down to the reflective lake, with patches of snow and clusters of yellow and blue flowers. Time to break out the cameras again. Beyond the lake, there is another very shallow, reflective tarn among the trees where you may be tempted to pause for photos again. From there, follow the trail back down to the trailhead. The entire circuit took us a leisurely 7 hours.
Links to other information, routes & trip reports for this peak that may be helpful.