Editing Potomac River (section)

==Course==
[[File:Potomac River in District of Columbia IMG 4720.JPG|thumb|The Potomac River in [[Washington, D.C.]], with [[Arlington Memorial Bridge]] in the foreground and [[Rosslyn, Arlington, Virginia]] in the background|right]]
The Potomac River runs {{cvt|405|mi}} from [[Fairfax Stone Historical Monument State Park]] in West Virginia on the [[Allegheny Plateau]] to [[Point Lookout, Maryland|Point Lookout]], Maryland, and drains {{cvt|14679|sqmi|km2}}. The length of the river from the junction of its North and South Branches to Point Lookout is {{cvt|302|mi}}.<ref name=NHD/>
[[File:Physiographic provinces of the Mid-Atlantic region by NPS.png|thumb|left|Map showing the five geological provinces through which the Potomac River flows<ref name="NPS-PH">{{cite web |url=https://www.nps.gov/pohe/learn/nature/geology.htm |title=Geology of Potomac Heritage National Scenic Trail |date=2019 |website=Potomac Heritage |publisher=NPS |access-date=25 March 2019 |archive-date=December 7, 2020 |archive-url=https://web.archive.org/web/20201207140412/https://www.nps.gov/pohe/learn/nature/geology.htm |url-status=live}}</ref>]]

The river has two sources. The source of the North Branch is at the Fairfax Stone located at the junction of [[Grant County, West Virginia|Grant]], [[Tucker County, West Virginia|Tucker]], and [[Preston County, West Virginia|Preston]] counties in [[West Virginia]]. The source of the South Branch is located near [[Hightown, Virginia|Hightown]] in northern [[Highland County, Virginia|Highland County]], Virginia. The river's two branches converge just east of [[Green Spring, West Virginia|Green Spring]] in [[Hampshire County, West Virginia|Hampshire County]], West Virginia, to form the Potomac. As it flows from its [[River source|headwaters]] down to the Chesapeake Bay, the Potomac traverses five geological provinces: the [[Appalachian Plateau]], the [[Ridge and Valley]], the [[Blue Ridge Mountains|Blue Ridge]], the [[Piedmont Plateau]], and the [[Atlantic coastal plain]].

Once the Potomac drops from the [[Piedmont (United States)|Piedmont]] to the [[Coastal Plain]] at the [[Atlantic Seaboard fall line]] at [[Little Falls (Potomac River)|Little Falls]], [[tides]] further influence the river as it passes through Washington, D.C., and beyond. [[Salinity]] in the [[#cnote PES|Potomac River Estuary]] increases thereafter with distance downstream. The [[estuary]] also widens, reaching 11 statute miles (17&nbsp;km) wide at its mouth, between Point Lookout, Maryland, and [[Smith Point Light|Smith Point]], Virginia, before flowing into the Chesapeake Bay.{{Potomac River routemap}}

===North Branch Potomac River===
{{Main|North Branch Potomac River}}
[[File:North Branch Potomac River Cumberland.jpg|thumb|left|The North Branch between [[Cumberland, Maryland]], and [[Ridgeley, West Virginia]], in 2007]]
The source of the North Branch Potomac River is at the [[Fairfax Stone]] located at the junction of [[Grant County, West Virginia|Grant]], [[Tucker County, West Virginia|Tucker]] and [[Preston County, West Virginia|Preston]] counties in West Virginia. From the Fairfax Stone, the North Branch Potomac River flows {{cvt|27|mi|km}} to the man-made [[Jennings Randolph Lake]], an [[Reservoir|impoundment]] designed for flood control and emergency water supply. Below the dam, the North Branch cuts a serpentine path through the eastern Allegheny Mountains. First, it flows northeast by the communities of [[Bloomington, Maryland|Bloomington]], [[Luke, Maryland|Luke]], and [[Westernport, Maryland|Westernport]] in Maryland and then on by [[Keyser, West Virginia|Keyser]], West Virginia to [[Cumberland, Maryland|Cumberland]], Maryland. At Cumberland, the river turns southeast. {{convert|103|mi}} downstream from its source,<ref name=NHD/> the North Branch is joined by the South Branch between [[Green Spring, West Virginia|Green Spring]] and [[South Branch Depot, West Virginia|South Branch Depot]], West Virginia from whence it flows past [[Hancock, Maryland|Hancock]], Maryland and turns southeast once more on its way toward [[Washington, D.C.]], and the [[Chesapeake Bay]].

===South Branch Potomac River===
{{Main|South Branch Potomac River}}
The South Branch's source is northwest of Hightown along [[U.S. Route 250]] on the eastern side of Lantz Mountain (3,934&nbsp;ft) in Highland County, Virginia. From Hightown, the South Branch is a small meandering [[stream]] that flows northeast along Blue Grass Valley Road through the communities of [[New Hampden, Virginia|New Hampden]] and [[Blue Grass, Virginia|Blue Grass]]. At [[Forks of Waters, Virginia|Forks of Waters]], the South Branch joins with Strait Creek and flows north across the Virginia/West Virginia border into [[Pendleton County, West Virginia|Pendleton County]].

The river then travels on a northeastern course along the western side of Jack Mountain (4,045&nbsp;ft), followed by Sandy Ridge (2,297&nbsp;ft) along [[U.S. Route 220]]. North of the confluence of the South Branch with Smith Creek, the river flows along Town Mountain (2,848&nbsp;ft) around [[Franklin, West Virginia|Franklin]] at the junction of U.S. Route 220 and [[U.S. Route 33]]. After Franklin, the South Branch continues north through the [[Monongahela National Forest]] to [[Upper Tract, West Virginia|Upper Tract]] where it joins with three sizeable streams: Reeds Creek, Mill Run, and Deer Run.

Between Big Mountain (2,582&nbsp;ft) and Cave Mountain (2,821&nbsp;ft), the South Branch bends around the Eagle Rock (1,483&nbsp;ft) outcrop and continues its flow northward into [[Grant County, West Virginia|Grant County]]. Into Grant, the South Branch follows the western side of Cave Mountain through the {{convert|20|mi|km|adj=on}} long [[Smoke Hole Canyon]], until its confluence with the [[North Fork South Branch Potomac River|North Fork]] at [[Cabins, West Virginia|Cabins]], where it flows east to [[Petersburg, West Virginia|Petersburg]]. At Petersburg, the [[South Branch Valley Railroad]] begins, which parallels the river until its mouth at [[Green Spring, West Virginia|Green Spring]].

[[File:Hanging Rocks Wappocomo WV 1890s.jpg|thumb|right|Canoeists at [[Hanging Rocks]] on the South Branch in the 1890s]]
In its eastern course from Petersburg into [[Hardy County, West Virginia|Hardy County]], the South Branch becomes more navigable allowing for [[canoes]] and smaller river vessels. The river splits and forms a series of large islands while it heads northeast to [[Moorefield, West Virginia|Moorefield]]. At Moorefield, the South Branch is joined by the [[South Fork South Branch Potomac River]] and runs north to [[Old Fields, West Virginia|Old Fields]] where it is fed by Anderson Run and Stony Run.

At [[McNeill, West Virginia|McNeill]], the South Branch flows into [[the Trough]] where it is bound to its west by [[Mill Creek Mountain]] (2,119&nbsp;ft) and to its east by Sawmill Ridge (1,644&nbsp;ft). This area is the habitat to [[bald eagles]]. The Trough passes into [[Hampshire County, West Virginia|Hampshire County]] and ends at its confluence with Sawmill Run south of [[Glebe, West Virginia|Glebe]] and [[Sector, West Virginia|Sector]].

The South Branch continues north parallel to [[South Branch River Road]] ([[county road|County Route]] 8) toward [[Romney, West Virginia|Romney]] with a number of historic plantation farms adjoining it. En route to Romney, the river is fed by Buffalo Run, [[Mill Run (South Branch Potomac River)|Mill Run]], McDowell Run, and [[Mill Creek (South Branch Potomac River)|Mill Creek]] at [[Vanderlip, West Virginia|Vanderlip]]. The South Branch is traversed by the [[Northwestern Turnpike]] ([[U.S. Route 50 in West Virginia|U.S. Route 50]]) and joined by Sulphur Spring Run where it forms [[Valley View Island]] to the west of town.

Flowing north of Romney, the river still follows the eastern side of Mill Creek Mountain until it creates a horseshoe bend at [[Wappocomo, West Virginia|Wappocomo]]'s [[Hanging Rocks]] around the George W. Washington plantation, [[Washington Bottom Farm|Ridgedale]]. To the west of [[Three Churches, West Virginia|Three Churches]] on the western side of [[South Branch Mountain]], {{convert|3,028|ft|m}}, the South Branch creates a series of bends and flows to the northeast by [[Springfield, West Virginia|Springfield]] through Blue's Ford. After two additional horseshoe bends (meanders), the South Branch flows under the old [[Baltimore and Ohio Railroad]] mainline between [[Green Spring, West Virginia|Green Spring]] and [[South Branch Depot, West Virginia|South Branch Depot]], and joins the North Branch to form the Potomac.

===Upper Potomac River===
This stretch encompasses the section of the Potomac River from the [[confluence]] of its North and South Branches through [[Opequon Creek]] near [[Shepherdstown, West Virginia]].<ref>{{cite web |url=https://www.potomacriverkeepernetwork.org/ |title=Potomac Riverkeeper Network |date=2019 |website=www.potomacriverkeepernetwork.org |publisher=Potomac Riverkeeper Network |access-date=25 March 2019 |archive-date=November 19, 2020 |archive-url=https://web.archive.org/web/20201119163153/https://www.potomacriverkeepernetwork.org/ |url-status=live}}</ref> Along the way the following tributaries drain into the Potomac: [[North Branch Potomac River]], [[South Branch Potomac River]], [[Town Creek (Potomac River)|Town Creek]], [[Little Cacapon River]], [[Sideling Hill Creek (Potomac River)|Sideling Hill Creek]], [[Cacapon River]], [[Sir Johns Run]], [[Warm Spring Run]], [[Tonoloway Creek]], [[Fifteenmile Creek (Potomac River)|Fifteenmile Creek]], [[Sleepy Creek]], [[Cherry Run]], [[Back Creek (Potomac River)|Back Creek]], [[Conococheague Creek]], and [[Opequon Creek]].

===Lower Potomac River===
[[File:Aerial Photo of Harpers Ferry (15646790473).jpg|thumb|left|Confluence of the Potomac and Shenandoah at Harpers Ferry]]
This section covers the Potomac from just above Harpers Ferry in West Virginia down to Little Falls, Maryland on the border between Maryland and Washington, DC. Along the way the following tributaries drain into the Potomac: [[Antietam Creek]], [[Shenandoah River]], [[Catoctin Creek (Virginia)]], [[Catoctin Creek (Maryland)]], [[Tuscarora Creek (Potomac River)|Tuscarora Creek]], [[Monocacy River]], [[Little Monocacy River]], [[Broad Run (Maryland)|Broad Run]], [[Goose Creek (Potomac River)|Goose Creek]], [[Broad Run (Loudoun County, Virginia)|Broad Run]], Horsepen Branch, [[Little Seneca Creek]], [[Tenmile Creek (Maryland)|Tenmile Creek]], [[Great Seneca Creek]], Old Sugarland Run, [[Muddy Branch]], Nichols Run, [[Watts Branch (Potomac River)|Watts Branch]], Limekiln Branch, Carroll Branch, Pond Run, Clarks Branch, Mine Run Branch, [[Difficult Run]], Bullneck Run, [[Rock Run (Potomac River)|Rock Run]], Scott Run, Dead Run, Turkey Run, [[Cabin John Creek (Potomac River)|Cabin John Creek]], Minnehaha Branch, and [[Little Falls Branch (Potomac River)|Little Falls Branch]].

===Tidal Potomac River===
[[File:2016-08-28 10 15 51 View southwest across the Potomac River from the south end of Cobb Island Road on Cobb Island, Charles County, Maryland.jpg|thumb|right|View southwest across the tidal Potomac River from the south end of [[Maryland Route 254|Cobb Island Road]] on [[Cobb Island (Maryland)|Cobb Island]], [[Charles County, Maryland]] ]]
The Tidal Potomac River lies below the [[Atlantic Seaboard fall line|Fall Line]]. This 108-mile (174-km) stretch encompasses the Potomac from a short distance below the [[Washington, DC]] - [[Montgomery County, Maryland|Montgomery County]] line, just downstream of the [[Little Falls of the Potomac River]], to the [[Chesapeake Bay]].<ref>{{cite web |title=Potomac River Basin Fact Sheet |url=https://www.potomacriver.org/wp-content/uploads/2014/11/Potomac-Basin-Fact-Sheet_Oct_2015.pdf |date=October 2015 |website=www.potomacriver.org |publisher=Interstate Commission on the Potomac River Basin (ICPRB) |access-date=28 March 2019 |archive-date=December 16, 2017 |archive-url=https://web.archive.org/web/20171216060733/http://www.potomacriver.org/wp-content/uploads/2014/11/Potomac-Basin-Fact-Sheet_Oct_2015.pdf |url-status=live}}</ref>
Along the way the following tributaries drain into the Potomac: [[Pimmit Run]], [[Gulf Branch]], [[Donaldson Run]], [[Windy Run]], [[Spout Run]], [[Maddox Branch]], [[Foundry Branch]], [[Rock Creek (Potomac River)|Rock Creek]], Rocky Run, [[Tiber Creek]], Roaches Run, [[Washington Channel]], [[Anacostia River]], [[Four Mile Run]], [[Oxon Creek]], [[Hunting Creek]], [[Broad Creek (Potomac River)|Broad Creek]], Henson Creek, Swan Creek, [[Piscataway Creek]], [[Little Hunting Creek]], [[Dogue Creek]], [[Accotink Creek]], [[Pohick Creek]], [[Pomonkey Creek]], [[Occoquan River]], [[Neabsco Creek]], [[Powell's Creek]], [[Mattawoman Creek]], [[Chicamuxen Creek]], [[Quantico Creek]], [[Little Creek (Potomac River)|Little Creek]], [[Chopawamsic Creek]], [[Tank Creek]], [[Aquia Creek]], [[Potomac Creek]], [[Nanjemoy Creek]], [[Chotank Creek]], [[Port Tobacco River]], [[Popes Creek (Maryland)|Popes Creek]], [[Gambo Creek]], [[Clifton Creek]], [[Piccowaxen Creek]], [[Upper Machodoc Creek]], [[Wicomico River (Maryland eastern shore)|Wicomico River]], [[Neale Sound|Cobb Island]], [[Monroe Creek]], [[Mattox Creek]], [[Popes Creek (Virginia)|Popes Creek]], [[Breton Bay, Leonardtown]], [[St. Marys River (Maryland)|St. Marys River]], [[Yeocomico River]], [[Coan River]], and [[Hull Creek (Potomac River)|Hull Creek]].