Millions of people visit the Grand Canyon each year, taking in the sweeping views from developed areas where they can stroll along the rim, grab a bite to eat and hop on a shuttle bus to other outlooks. The proposals for backcountry management also address more remote areas of the park and relatively new recreation activities such as canyoneering, climbing, rim-to-rim excursions and backpacking trips that require short travel on the Colorado River. The park's preferred option for the backcountry management plan includes reducing group sizes for overnight backpacking, developing more campsites and limiting commercially guided services. A proposed pilot program also would allow seasonal access to a limited number of backpackers to a coveted area of canyons, buttes and a natural bridge beyond a formation known as the Great Thumb.