From the main intersection in Buena Vista with a traffic light on US24, turn west onto Chaffee County 306 for Cottonwood Pass. Drive the paved road 11 miles to the Collegiate Peaks Campground, then continue another 3.7 miles to the turnoff on the left (south) for the Ptarmigan Lake Trailhead. A short road leads into the trees to a paved parking lot able to handle a dozen vehicles. There's a vault toilet here. See coordinates below. The turn is easy to miss. The trail begins on the south side of the lot. It drops down to cross Middle Cottonwood Creek on a bridge.
The Denny Creek parking area, which serves as a primary access for Mt. Yale, is 1.1 mile past the campground. When continuing past that parking area, note that if using the 1982 Mt. Yale quad, the highway no longer makes the double switchback as shown on the map just west of Denny Creek. Also, do not confuse Denny Gulch with Denny Creek. The Gulch is located just across from the campground.
At between 13.9 and 14.0 miles west of Buena Vista on CR 306, there's a road that turns off to the south (left). Coordinates are: N 38° 48' 31.23 W 106° 21' 55.04". This is CR 346. A short drive down this road brings one to a locked gate, but this road continues and can be hiked as an alternate to the Ptarmigan Lake Trail. This road will eventually intersect that trail as shown on some maps. We mention this road because we have been able to car-camp on this road at the locked gate. If all other camp spots including the Collegiate Peaks CG are full, this may be a convenient and unused spot to camp for hiking Turner Peak or Jones Mountain.
The Nearest Forest Service campground is the Collegiate Peaks CG, located at 11 miles west of Buena Vista. This Fee facility has water and vault toilets. Latest cost is $20.00 and reservations are accepted. Reserved weekend sites must be reserved for both Friday & Saturday evenings, but walk-ins are not restricted to this requirement. There are 56 sites here. No hook-ups for trailers, RV's etc. This campground is usually full on summer weekends. Plan accordingly. See this link for more information: https://www.fs.usda.gov/recarea/psicc/recarea/?recid=12648. There are other at-large sites along the Cottonwood Pass road, but be aware of private property issues. Technically, the Denny Creek and Ptarmigan Lake trailheads do not allow "overnight" camping. See instructions above for another spot to car-camp.
Near the "Holywater" Beaver Ponds, there's a couple of pull-outs on either side of the highway. We are not sure what the intended use of these are. They are paved and can accommodate a number of vehicles - perhaps intended for overflow parking or access to the ponds. They we not posted restricting overnight camping when we investigated, but being right on the side of the highway, we opted to not attempt to use them.