Question: How long is the mountain range that includes Turner's Gap?

Context paragraphs:
Gap Mountains: The Gap Mountains are a mountain range in eastern Nye County, Nevada.  Gap Mountain along with Fox Mountain 7.5 mi to the south and the hills between overlook the White River valley to the west.  Gap Mountain lies just 1.5 mi southwest of the southern end of the Egan Range of adjacent Lincoln County and appears to be an extension of that range.  Fox Mountain lies about 5 miles west of the south end of the Schell Creek Range and 7 mi northeast of the north end of the Seaman Range. The Grant Range and small Golden Gate Range lie to the west across the White River Valley.

Coast Mountains: The Coast Mountains are a major mountain range in the Pacific Coast Ranges of western North America, extending from southwestern Yukon through the Alaska Panhandle and virtually all of the Coast of British Columbia south to the Fraser River.  The mountain range's name derives from its proximity to the sea coast, and it is often referred to as the Coast Range.  The range includes volcanic and non-volcanic mountains and the extensive ice fields of the Pacific and Boundary Ranges, and the northern end of the volcanic system known as the Cascade Volcanoes.  The Coast Mountains are part of a larger mountain system called the Pacific Coast Ranges or the Pacific Mountain System, which includes the Cascade Range, the Insular Mountains, the Olympic Mountains, the Oregon Coast Range, the California Coast Ranges, the Saint Elias Mountains and the Chugach Mountains.  The Coast Mountains are also part of the American Cordilleraa Spanish term for an extensive chain of mountain rangesthat consists of an almost continuous sequence of mountain ranges that form the western backbone of North America, Central America, South America and Antarctica.

Považský Inovec: Považský Inovec is a mountain range in western Slovakia, named after the Váh river.  It is 48 km (30 mi) long and 15–25 km (9-16 mi) wide mountain range.  It is situated from the city of Hlohovec, raising from the Danubian Hills, and slowly raising further north until nearly to the city of Trenčín where it borders the Strážov Mountains, where is also the highest hill of the entire mountain range, "Inovec" (1042 m).  The mountain range separates basins of the Váh and Nitra rivers.

Turner's and Fox's Gaps Historic District: The Turner's and Fox's Gaps Historic District comprises the Civil War-era battlefield involved in the Battle of South Mountain, which took place on September 14, 1862.  The district extends on the west to the slopes of South Mountain in the area of Zittlestown, and to the east beyond the foot of the mountain to the small community of Bolivar.  The district is characterized by steep mountain terrain in the west and open farmland in the east, with Turner's Gap to the north and Fox's Gap to the south.  The district includes 115 contributing buildings and structures.  The most significant contributing buildings are the Mountain House Inn (now the Old South Mountain Inn) and the White House Inn, or Beachley House.  Also included in the list is the Reno Monument at Fox's Gap, shown at right.  The Old National Pike, now known as U.S. 40 Alternate, passes over South Mountain at Turner's Gap.

South Mountain (Maryland and Pennsylvania): South Mountain is the northern extension of the Blue Ridge Mountain range in Maryland and Pennsylvania.  From the Potomac River near Knoxville, Maryland, in the south, to Dillsburg, Pennsylvania, in the north, the 70 mi range separates the Hagerstown and Cumberland valleys from the Piedmont regions of the two states.  The Appalachian National Scenic Trail follows the crest of the mountain through Maryland and a portion of Pennsylvania.

Breheimen: Breheimen is a mountain range in the Sogn og Fjordane and Oppland counties in Norway.  The area lies west of the Jotunheimen mountain range.  The mountain range lies to the northwest of the Sognefjellsvegen road, north of the Sognefjorden, south of the Nordfjorden and Norwegian National Road 15, and east of Norwegian National Road 5 and European route E39.  The mountain range includes Jostedalsbreen National Park and Breheimen National Park.

Chhuxlla Willk'i: Chhuxlla Willk'i (Aymara "chhuxlla" grass, weed, pasture or a kind of barley, "willk'i" gap, "pasture gap" or "barley gap", also spelled "Chojlla Willkhi") is a 4664 m mountain in the Chilla-Kimsa Chata mountain range in the Andes of Bolivia.  It lies in the La Paz Department, Ingavi Province, Jesús de Machaca Municipality.  Chhuxlla Willk'i is situated south-east of the 4737 m mountain named Qala Cruz "(Khala Cruz)" and Ch'alla Qullu ("sand mountain", "Challa Kkollu"), and north-east of a 4522 m mountain which is also called Qala Cruz.

Wind River Range: The Wind River Range (or "Winds" for short), is a mountain range of the Rocky Mountains in western Wyoming in the United States.  The range runs roughly NW-SE for approximately 100 miles (161 km).  The Continental Divide follows the crest of the range and includes Gannett Peak, which at 13,804 feet (4,207 m), is the highest peak in Wyoming.  There are more than 40 other named peaks in excess of 13,000 feet (3,962 m).  With the exception of the Grand Teton in the Teton Range, the next 19 highest peaks in Wyoming after Gannett are also in the Winds.  Two large National Forests including three wilderness areas encompass most of the mountain range.  Shoshone National Forest is on the eastern side of the continental divide while Bridger-Teton National Forest is on the west.  Both National Forests and the entire mountain range are an integral part of the Greater Yellowstone Ecosystem.  Portions of the range are also inside the Wind River Indian Reservation.

Chehalem Mountains: The Chehalem Mountains are a mountain range located in the Willamette Valley in the U.S. state of Oregon.  Forming the southern boundary of the Tualatin Valley, the Chehalems are the highest mountains in the Willamette Valley.  Composed of a single land mass that was uplifted by tectonic forces, the mountain range includes several spurs and ridges such as Parrett Mountain, Ribbon Ridge, and Bald Peak.  The range extends from the Willamette River east of Newberg northwest to the foothills of the Oregon Coast Range south of Forest Grove.  The highest peak in the Chehalem Mountain Range is Bald Peak, rising to 1629 ft , which is also the highest peak point within the Willamette Valley.

Turner's Gap: Turner's Gap is a wind gap in the South Mountain Range of the Blue Ridge Mountains, located in Frederick County and Washington County, Maryland.  The gap is traversed by U.S. Route 40 Alternate, the old National Pike.  The Appalachian Trail also crosses the gap.

Supporting paragraphs: Turner's Gap South Mountain (Maryland and Pennsylvania)
Answer: 70 mi