The Appalachian Mountains run along eastern North America from Belle Isle off the coast of Newfoundland, Canada, southwest roughly 2,000 miles (about 3,200 kilometers) to Flagg Mountain in central Alabama, USA. The range crosses six Canadian provinces and 13 U.S. states. Its broadest span, near Pennsylvania and Maryland, reaches roughly 300 miles from the Valley and Ridge to the coastal plain. The highest point is 6,684-foot Mount Mitchell in North Carolina. The Appalachian Trail, a 2,190-mile footpath, follows the crest through 14 states and is the range's best-known spine.
Where the Range Begins and Ends
Geographers define the Appalachian Mountains in two ways, and the difference matters. The geologic province extends from Newfoundland to Alabama. The physiographic definition used by U.S. agencies draws the northern boundary in New York and southern Canada. Both agree the chain trends southwest-northeast, parallel to the Atlantic coast, from about 49 degrees north latitude down to roughly 33 degrees north.
In Canada, the range passes through Newfoundland and Labrador, Quebec, New Brunswick, Nova Scotia, Prince Edward Island, and Ontario in its broad geologic sense. Maritime Canada holds the northern terminus at Belle Isle. The Notre Dame and Long Range mountains of Newfoundland are ancient, heavily glaciated remnants of the same orogeny that built the southern highlands.
In the United States, the chain runs through Alabama, Georgia, South Carolina, North Carolina, Tennessee, Virginia, West Virginia, Kentucky, Ohio, Maryland, Pennsylvania, New Jersey, New York, Connecticut, Massachusetts, Vermont, New Hampshire, and Maine. The Appalachian Trail's 14 states are the practical travel definition: Georgia, North Carolina, Tennessee, Virginia, West Virginia, Maryland, Pennsylvania, New Jersey, New York, Connecticut, Massachusetts, Vermont, New Hampshire, and Maine.
The southern end is debated. Most maps place it at Flagg Mountain in Coosa County, Alabama, near the trail's southern terminus at Springer Mountain, Georgia. A minority view pushes the range into the Red Mountain and Birmingham area, where isolated ridges continue the trend. The northern end is cleaner: Belle Isle, Newfoundland, lies at the northeast tip of the Long Range.
How the Mountains Got Where They Are
The Appalachians are a stack of mountain belts welded onto the eastern edge of ancient North America over roughly 1.1 billion years. The oldest events, around 1.1 billion years ago, built the Grenville province, whose metamorphic rocks appear in the Blue Ridge and Adirondacks. The Adirondacks in New York are technically part of that Grenville basement, not the later fold belts, which explains why they sit oddly northwest of the main spine.
The modern architecture came from three orogenies, the Taconic (roughly 470–440 million years ago), the Acadian (roughly 420–380 million years ago), and the Alleghanian (roughly 325–265 million years ago). Each was a collision: an island arc, then a microcontinent called Avalon, then Africa itself. The Alleghanian collision, the climactic one, compressed the crust into folds and thrust sheets that stacked rock westward across what is now the Valley and Ridge province.
That compression is why the range trends northeast-southwest: the collision pushed perpendicular to the ancient margin. It is also why the fold belts run parallel to the coast today. The same squeeze that built the Appalachians built the Atlas Mountains of Morocco, because North America and Africa were joined in the supercontinent Pangaea. When Pangaea rifted apart roughly 200 million years ago, the Appalachians were split: the Moroccan Atlas kept a piece of the same belt.
After the collisions stopped, erosion took over. The original peaks may have rivaled the Himalayas, with estimates for the Alleghanian belt reaching 5 to 8 kilometers of structural relief before erosion. Today's topography, the ridges and valleys, reflects differential erosion: resistant quartzite and sandstone stand as ridges, while shale and limestone valleys erode faster.
A counterintuitive point: the Appalachians are not a single mountain chain but a chain of provinces, each with a different structure. The Blue Ridge, the Valley and Ridge, the Appalachian Plateau, the Piedmont, and the New England province all belong to the system, and they behave differently in erosion, groundwater, and landslide risk.
The Provinces in Numbers
The physiographic provinces run from southeast to northwest with distinct widths and elevations. The Piedmont, a broad lower plateau east of the mountains, spans roughly 100 to 200 miles in width. The Blue Ridge, the crystalline core, reaches its highest elevations at Mount Mitchell. The Valley and Ridge, the folded belt, is the classic ridge-and-valley landscape of Pennsylvania and Virginia. The Appalachian Plateau, the western margin, forms the Allegheny and Cumberland plateaus.
| Province | Typical width | Peak elevation example | Character |
|---|---|---|---|
| Piedmont | 100–200 mi | 1,500–2,000 ft | Rolling crystalline upland |
| Blue Ridge | 5–50 mi | 6,684 ft (Mount Mitchell) | Highest crest, steep front |
| Valley and Ridge | 30–80 mi | 3,000–4,500 ft | Parallel ridges and valleys |
| Appalachian Plateau | 100–300 mi | 4,863 ft (Spruce Knob) | Dissected plateau, coal-bearing |
| New England province | Variable | 6,288 ft (Mount Washington) | Glaciated northern highlands |
The highest summits cluster in the southern Blue Ridge: Mount Mitchell (6,684 feet), Mount Craig (6,647 feet), Clingmans Dome (6,643 feet), and Mount Guyot (6,621 feet). Spruce Knob in West Virginia is the highest point in that state at 4,863 feet. Mount Washington in New Hampshire reaches 6,288 feet and holds the record for a wind speed measured by a weather station at 231 miles per hour.
The Appalachian Trail's elevation profile runs from roughly 4,400 feet at Springer Mountain to 6,643 feet at Clingmans Dome and back down, with total climbing estimated at over 400,000 feet along its 2,190 miles. That figure matters for practical planning: southbound and northbound hikers face different sequencing of the highest terrain.
Edge Cases: What Counts as Appalachian
The boundary problem appears in three places. First, the Adirondacks: geologically Grenville basement, physiographically separate from the fold belts, sometimes excluded from the Appalachian system. Second, the eastern Piedmont: a broad upland that is Appalachian in origin but not mountainous in relief. Third, the western plateau: coal-bearing and Appalachian in structure but characterized by plateaus rather than peaks.
The Ozarks and Ouachitas of Arkansas and Missouri are sometimes called "little Appalachians" because they share fold-and-thrust geology, but they belong to a separate Paleozoic belt. The Black Mountains of North Carolina, home to Mount Mitchell, are a sub-range of the Blue Ridge, not a separate province. The Catskills of New York are a dissected plateau, not folded mountains, and are usually classed as part of the Appalachian Plateau's northern extension.
Names matter in navigation. The "Appalachian Plateau" in the official physiographic scheme includes the Allegheny Plateau, the Cumberland Plateau, and the Kanawha section. A traveler asking where the mountains are may be standing on a plateau 2,000 feet above sea level and still be within the system.
Practical Ways to Locate the Range
For a hiker, the crest of the Appalachian Trail is the simplest locator: the trail stays within the range for its full 2,190 miles. For a driver, Interstate 81 and Interstate 77 cross the Valley and Ridge and Blue Ridge respectively. For a pilot, the ridge-and-valley texture is unmistakable from altitude: parallel wooded ridges with farmed valleys between them.
A few concrete steps help confirm location:
Check the state: any of the 18 U.S. states and 6 Canadian provinces listed above contains Appalachian terrain. Look for the northeast-southwest trend: ridges and valleys align that way in the fold belt. Check elevation: the range rises from near sea level at its margins to 6,684 feet at Mount Mitchell. Use the trail corridor: within roughly 10 miles of the Appalachian Trail, you are in the mountains. Watch for quartzite and sandstone ridges: these rock types form the resistant crests. Distinguish plateau from peak: a flat upland 2,000 feet high can still be Appalachian Plateau.
Red-flag cautions for trip planning:
The southern terminus at Springer Mountain is remote; cell coverage is unreliable. Mount Washington's weather can change from clear to lethal within an hour. Valley and Ridge roads flood in heavy rain; low-water crossings become impassable. Winter ice closes parts of the Blue Ridge Parkway and the higher trail sections. Private land interrupts some ridge corridors; stay on marked routes.
Common Misconceptions
The biggest misconception is that the Appalachians are old and therefore gentle everywhere. Age predicts erodibility, not hazard: steep slopes in the Blue Ridge and White Mountains still produce landslides and rockfall, and the range's seismic zones include the Central Virginia seismic zone, which produced a magnitude 5.8 earthquake in 2011.
A second misconception is that the mountains end at the Mason-Dixon Line. They continue through Pennsylvania's Ridge and Valley, across New Jersey and New York, and up through New England into Canada. The chain does not terminate at any state border.
A third is that the Appalachian Trail defines the range. The trail is a footpath, not a geologic boundary; it follows the crest where possible but detours around terrain and private land. A fourth is that the highest point is in New Hampshire or Maine. Mount Mitchell in North Carolina is 396 feet higher than Mount Washington.
A professional caveat: physiographic province maps disagree at the margins, and agencies use different conventions. The U.S. Geological Survey's physiographic divisions place the Appalachian Highlands boundary in New York and southern Canada; Canadian geological surveys extend the Appalachian Orogen to Newfoundland. A reader comparing maps may see the range start and stop in different places, and both can be correct under their stated definitions.
Timeline of the Range
| Time (million years ago) | Event | Result today |
|---|---|---|
| ~1,100 | Grenville orogeny | Basement rocks of Blue Ridge and Adirondacks |
| ~470–440 | Taconic orogeny | First fold belt, eastern Piedmont |
| ~420–380 | Acadian orogeny | Northern New England, Maritime Canada |
| ~325–265 | Alleghanian orogeny | Valley and Ridge folds, thrust sheets |
| ~250–200 | Pangaea rifting | Range split from Atlas Mountains |
| ~2.6–0.01 | Pleistocene glaciation | Northern U-shaped valleys, cirques |
| Present | Erosion and uplift | Modern ridges, valleys, and trail crest |
The timeline explains a practical fact: the further north you go, the more glacial sculpting dominates. New England's valleys are U-shaped and its peaks are rounded or plucked by ice; the southern Blue Ridge retains sharper, older erosional forms.
What the Range Means for Residents and Visitors
The Appalachian Mountains supply drinking water to tens of millions of people in the eastern United States. The headwaters of the Tennessee, Ohio, Potomac, Delaware, and Hudson rivers rise in or near the range. Their forested slopes slow runoff and filter sediment, which is why reservoir management in the region depends on upland land cover.
The range also shapes weather. Orographic lift wrings moisture from prevailing westerlies, producing wet windward slopes and drier valleys. The southern Appalachians are among the most biologically diverse temperate forests in the world, with salamander diversity in the Great Smoky Mountains exceeding that of any comparable area.
For visitors, the practical limits are seasonal and spatial. The trail corridor is most crowded in spring and fall, and the highest terrain is most accessible from June through September. The Blue Ridge Parkway and Skyline Drive close in ice and fog. The northern highlands carry the harshest weather; Mount Washington's summit has recorded temperatures well below freezing in every month.
The range's extent also affects how people use the term. A resident of Birmingham, Alabama, may say they live "in the foothills of the Appalachians," while a geologist would place them near the southern terminus of the fold belt. A resident of Montreal is in the Appalachian geologic province but not in the mountains. Precision comes from naming the province, not just the range.
One more caveat: the range is not static. Erosion continues, and isostatic rebound after glaciation still lifts parts of New England. The mountains are old, but they are still moving in slow motion, which is why the answer to where they are includes both a map and a clock.