The Appalachian Mountains, often called the Appalachians, are a system of mountains in eastern to northeastern North America. The Appalachians first formed roughly 480 million years ago during the Ordovician Period. They once reached elevations similar to those of the Alps and the Rocky Mountains before experiencing natural erosion. The Appalachian chain is a barrier to east–west travel, as it forms a series of alternating ridgelines and valleys oriented in opposition to most highways and railroads running east–west.
Sullivan County is a county in the Commonwealth of Pennsylvania. It is part of Northeastern Pennsylvania. As of the 2020 census, the population was 5,840, making it the second-least populous county in Pennsylvania. Its county seat is Laporte. The county was created on March 15, 1847, from part of Lycoming County and named for Major General John Sullivan.
The Catskill Mountains, also known as the Catskills, are a physiographic province of the larger Appalachian Mountains, located in southeastern New York. As a cultural and geographic region, the Catskills are generally defined as those areas close to or within the borders of the Catskill Park, a 700,000-acre (2,800 km2) forest preserve protected from many forms of development under New York state law.
The Allegheny Mountain Range, informally the Alleghenies, is part of the vast Appalachian Mountain Range of the Eastern United States and Canada and posed a significant barrier to land travel in less developed eras. The Allegheny Mountains have a northeast–southwest orientation, running for about 400 miles (640 km) from north-central Pennsylvania, southward through western Maryland and eastern West Virginia.
The Cumberland Plateau is the southern part of the Appalachian Plateau in the Appalachian Mountains of the United States. It includes much of eastern Kentucky and Tennessee, and portions of northern Alabama and northwest Georgia. The terms "Allegheny Plateau" and the "Cumberland Plateau" both refer to the dissected plateau lands lying west of the main Appalachian Mountains. The terms stem from historical usage rather than geological difference, so there is no strict dividing line between the two. Two major rivers share the names of the plateaus, with the Allegheny River rising in the Allegheny Plateau and the Cumberland River rising in the Cumberland Plateau in Harlan County, Kentucky.
The Allegheny Plateau is a large dissected plateau area of the Appalachian Mountains in western and central New York, northern and western Pennsylvania, northern and western West Virginia, and eastern Ohio. It is divided into the unglaciated Allegheny Plateau and the glaciated Allegheny Plateau.
The Ridge-and-Valley Appalachians, also called the Ridge and Valley Province or the Valley and Ridge Appalachians, are a physiographic province of the larger Appalachian division and are also a belt within the Appalachian Mountains extending from southeastern New York in the north through northwestern New Jersey, westward into Pennsylvania through the Lehigh Valley, and southward into Maryland, West Virginia, Virginia, Kentucky, Tennessee, Georgia, and Alabama. They form a broad arc between the Blue Ridge Mountains and the Appalachian Plateau physiographic province. They are characterized by long, even ridges, with long, continuous valleys in between.
The Allegheny Front is the major southeast- or east-facing escarpment in the Allegheny Mountains in southern Pennsylvania, western Maryland, eastern West Virginia, and western Virginia, USA. The Allegheny Front forms the boundary between the Ridge-and-Valley Appalachians to its east and the Appalachian Plateau to its west. The Front is closely associated with the Appalachian Mountains' Eastern Continental Divide, which in this area divides the waters of the Ohio/Mississippi river system, flowing to the Gulf of Mexico, from rivers flowing into Chesapeake Bay and from there into the Atlantic Ocean.
The Appalachian Plateau is a series of rugged dissected plateaus located on the western side of the Appalachian Mountains. The Appalachian Mountains are a mountain range that run down the Eastern United States.
North Mountain is a peak in the Catskill Mountains of New York, on the border between the towns of Catskill and Hunter, in Greene County. It is part of the Catskill Escarpment. Cairo Round Top is located northeast and Artists Rock is located southeast of North Mountain.
The Potomac Highlands of West Virginia centers on five West Virginian counties in the upper Potomac River watershed in the western portion of the state's Eastern Panhandle, bordering Maryland and Virginia. Because of geographical proximity, similar topography and landscapes, and shared culture and history, the Potomac Highlands region also includes Pocahontas, Randolph, and Tucker counties, even though they are in the Monongahela River or New River watersheds and not that of the Potomac River.
Wills Mountain is a quartzite-capped ridge in the Ridge and Valley physiographic province of the Appalachian Mountains in Pennsylvania and Maryland, United States, extending from near Bedford, Pennsylvania, to near Cumberland, Maryland. It is the northernmost of several mountain ridges included within the Wills Mountain Anticline.
Dans Mountain is located in Allegany County, Maryland, USA between Georges Creek and the North Branch Potomac River. The highest point on Dans Mountain is called Dan's Rock which has an elevation of 2,895 feet (882 m). The mountain rises 2,200 feet (670 m) above the town of LaVale and the summit is the highest point in Allegany County. Although there are higher points in Maryland, Dans Mountain has the most impressive escarpment of Maryland's mountains. It is essentially continuous with the longer escarpment that continues both north and south known as the Allegheny Front.
Blue Knob is a summit in the eastern United States with a broad dome that is the northernmost 3,000-footer in the Allegheny Mountains. It is the highest point in Bedford County, Pennsylvania.
The Geology of Pennsylvania consists of six distinct physiographic provinces, three of which are subdivided into different sections. Each province has its own economic advantages and geologic hazards and plays an important role in shaping everyday life in the state. From the southeast corner to the northwest corner of the state, the include: the Atlantic Plain Province province, the Piedmont Province, the New England Province, the Ridge and Valley Province, the Appalachain Province, and the Central Lowlands Province.
Camelback Mountain or Big Pocono is a conspicuous geographic feature on the Pocono Plateau. It is not a mountain, but rather a peninsular section of the Pocono Plateau, that when viewed from three sides, appears to be a mountain. The summit of Big Pocono "Mountain" is actually nearly level with land to the west and northwest, together comprising the top of the Glaciated Pocono Plateau, which is part of the larger Allegheny Plateau.
Elk Hill, also known as North Knob or Elk Mountain, is a mountain in Herrick Township, Pennsylvania. It is the highest mountain peak in Pennsylvania east of the Susquehanna River and the highest peak on the Allegheny Plateau.
Spruce Mountain, located in eastern West Virginia, is the highest ridge of the Allegheny Mountains. The whale-backed ridge extends for only 16 miles (26 km) from northeast to southwest, but several of its peaks exceed 4,500 feet (1,400 m) in elevation. The summit, Spruce Knob, is the highest Allegheny Mountain point both in the state and the entire range, which spans four states.
Blair Gap, one of the gaps of the Allegheny, is a water gap along the eastern face atop the Allegheny Front escarpment. Like other gaps of the Allegheny, the slopes of Blair Gap were amenable to foot travel, pack mules, and possibly wagons allowing Amerindians, and then, after about 1778-1780 settlers, to travel west into the relatively depopulated Ohio Country decades before the railroads were born and tied the country together with steel.
The gaps of the Allegheny, meaning gaps in the Allegheny Ridge in west-central Pennsylvania, is a series of escarpment eroding water gaps along the saddle between two higher barrier ridge-lines in the eastern face atop the Allegheny Ridge or Allegheny Front escarpment. The front extends south through Western Maryland and forms much of the border between Virginia and West Virginia, in part explaining the difference in cultures between those two post-Civil War states. While not totally impenetrable to daring and energetic travelers on foot, passing the front outside of the water gaps with even sure footed mules was nearly impossible without navigating terrain where climbing was necessary on slopes even burros would find extremely difficult.
