There are roughly 270 shelters along the length of the AT, spaced an average of 7-8 miles apart. The typical shelter is square, one-story, garage-sized, wooden, three-sided with the fourth side open to the elements, and covered by a large overhanging roof. There may be picnic tables or benches under the overhang. However some shelters are made of stone, multi-story, or have porches. Nearly every one is close to a water source like a spring or creek, and has a detached privy. Most shelters are first-come, first-serve, with an exception in Great Smokey Mountains NP (see below).
Benefits to Shelters
Since nearly every shelter is close to a water source and has a privy, most thru-hikers stop and stay at shelters. They are also the best places to get out of the rain on the drizzly AT and there is a psychological benefit to being able to sit down and cook dinner on a dry bench, rather than on the ground in the mud.
Shelters also concentrate human impacts on the environment around the immediate vicinity of the shelter. The ATC touts this concentration as impact "reduction" as thus a benefit, though this is the exact opposite of the philosophy governing the Pacific Crest Trail.
Centers of Trail Life
Shelters are the centers of social life on the AT. Because of obvious draws like privies, water, and a dry place to sit down, hikers congregate at them where they chat and get to know each other. Hikers with similar paces often end up at the same shelters every night for weeks at a time. Additionally, every shelter contains a register — a notebook where hikers record thoughts like in a journal, or write messages to friends who are behind them. Like a popular blog, many hikers read entries by consistent writers who they may not know personally.
Camping Happens Around Shelters
Shelters fill up fast, but even when they don't many hikers prefer the privacy of their tents. They may cook dinner and hang out at the shelter for a while then retire to their tent when ready for bed. It is possible to tent in the immediate vicinity of every shelter, though in the Smokies there are a few caveats (see below).
Is Thru-Hiking Without a Tent Possible?
People often ask whether they can expect to sleep in a shelter every night and thus won't need a tent. The temptation to save weight seems to motivate this line of thinking, but while hypothetically possible, it's more difficult than you might imagine and we don't recommend trying it both for both practical and safety reasons.
The ATC would prefer that hikers tent at shelters so as to concentrate the human impact on the land to shelter locations — a complete opposite of the philosophy that dominates the Pacific Crest Trail, where there are no shelters or designated campsites and the PCTA encourages dispersed camping. Other than the immediate vicinity of shelters, there are not many "official" or designated tentsites on the AT.
Where to Pitch a Tent
Most of the time, especially in the National Forests, it's legal to pitch a tent anywhere along the trail. However, tenting regulations vary, so check the AWOL guidebook to make sure it's legal to pitch where you are at. In practice, terrain and water sources more than legal restrictions have dictated the location of tent sites, and every good spot was found years ago. These sites have been used for so long and are so established (with logs arranged in a circle, firepits, et cetera) that they are in effect, official tensites. They are listed in AWOL's guidebook but rarely appear in the ATC's databook — another reason not to buy the databook.
Follow Leave No Trace Principles
When you tent in locations other than a shelter, official campsite, or long-established campsite, follow Leave No Trace principles: Camp out of sight of the trail and at least 200 feet from any water source. Avoid spots that show evidence of past use but where plants can still recover and grow back. Always pitch your tent on dead leaves, bare soil, or grass, and never trample plants.
Great Smokey Mountains National Park (Tennessee/North Carolina)
GSMNP regulations require regular hikers (not thru-hikers) to sleep in shelters. Tenting is not allowed except at the Birch Spring Gap campsite. Regular hikers must also make reservations for shelters.
Thru-hikers do not have to make reservations for shelters but are still required to sleep in them unless a shelter is full. Only then can a thru-hiker tent in the immediate vicinity of the shelter. Tenting is not allowed anywhere else along the trail in the Park. From March 15 to June 15, four spaces at each AT shelter are reserved for thru-hikers. Since only thru-hikers are allowed to tent next to shelters, they are required to make room for those who have reservations.
The Park Service defines a thru-hiker as someone who begins and ends their hike at least 50 miles outside the park and only travels on the AT while in the park. Thru-hikers are also required to have an AT thru-hiker's permit, which costs $20 and is discussed on the permits and fees page.
Shenandoah National Park (Virginia)
There are two types of structures along the AT in the Park, ones for day-use and ones for overnight use. Annoyingly, Shenandoah screws up the naming system and calls the day-use structures "shelters" and the overnight structures "huts." Tenting/camping at the day-use "shelters" is not allowed. The AWOL guidebook distinguishes between the two so there shouldn't be any confusion.
"Huts" are available to thru-hikers at a first-come, first serve basis like usual. Tenting at huts is allowed in designated spots. Every hut has designated tentsites. When first entering the park, thru-hikers are required to obtain a free backcountry permit from an on-trail kiosk. Details are discussed on the permits and fees page.
Green Mountain National Forest (Vermont)
There are fees to camp at some high-use campsites. A Green Mountain Club caretaker may be present at other sites, but a fee is not charged. No permits or reservations are required.
The White Mountains (New Hampshire)