Because ski area procedures and policies change from year to year, you may need to update this information with your own research. Because the various foot approaches to Mt. Jackson involve a significant number of hiking miles, our proposed approach reduces this climb to the least number of hiking miles possible. Whether or not you choose to use this approach may depend on how you feel about the legitimacy of using a ski lift to get you part way up a mountain.
From I-70, take the main Avon exit and drive south through 4 traffic circles south of the interstate. At the 4th circle, exit west on old Highway 6 and drive a short distance to a large parking lot that serves the ski area. You may want to call the ski area and/or local police in advance to check their policies in regards to leaving a vehicle parked here overnight. From the parking lot, catch the next shuttle bus up to the base of the Beaver Creek Ski Area with your loaded pack in tow. Locate the window for purchasing a lift ticket and make whatever purchase will get you highest on the mountain. In the two years we did this, (1995 & 2002) we rode the "Centennial Express Lift" to the Spruce Saddle Lodge at 10,200 ft. In 2002, this cost us $16 each. In 1995, we were able to obtain a "family day pass." In both years, the pass would be good for a 24 hour period so we could ride up one day and catch the lift down the next day before it closed. Whatever pass they issue now, check carefully to see if you'll be able to use it the next day.
Once aboard the lift, enjoy the brief ride that will save you 2 miles of packing and about 2,000 ft. in elevation gain. Assuming that the Spruce Saddle Lodge is as far as you can ride, depart from here and begin your hiking or backpacking adventure. Begin by hiking under lift #8, the "Cinch Express Lift" and follow it on moderate uphill terrain to the top of the ski mountain at 11,440 ft. This will take about one hour. A little west of the lift station, a dirt road leads into the forest to a microwave station. From the station, we found a faint, cairn-marked trail that continued south through trees. A clearing at 11, 560 ft. is about where you'll encounter the wilderness boundary, marked by stakes. A little after there, you'll exit the trees for open ridge hiking. Continue hiking south along the ridge crest on mostly tundra with some rocks and possibly patches of snow in earlier season. Just past the point marked 12,161 ft., the ridge descends some. We found some grassy spots to camp on just below two closed contour marks of 12,000 ft. This will be south of and about 400 feet above Waterdog Lake. It's also possible to descend further to the saddle and find some campsites in the trees. It takes another hour from the top lift to arrive here. Expect mosquitoes, but camping higher on the open ridge will expose you to some breezes that may keep some of the mosquitoes away. From a campsite on the open ridge, you may have a view further south of the western flank of Grouse Mountain where in previous years, a very large herd of elk could be observed.
Do not expect to find any convenient, overnight camping anywhere near around Avon. Both times we've done this trip, we did it as an overnight backpack, so the one night of camping was on the high ridge north of Grouse Mountain, as described above. There, you will be on wilderness land with no camping restrictions unless there's a fire ban.