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Layer: PHNST Trail - Main/Alternative (ID:9)

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Name: PHNST Trail - Main/Alternative

Display Field: Name

Type: Feature Layer

Geometry Type: esriGeometryPolyline

Description: The creation of the Potomac Heritage National Scenic Trail (PHNST) GIS feature layer was a cooperative effort among the National Park Service, trail management stakeholders, and the jurisdictions that are represented by the Northern Virginia Regional Commission (NVRC). The Potomac Heritage National Scenic Trail (PHNST) is a partially existing trail that generally follows the Potomac River. When the Northern Virginia portion of the trail is completed it will connect northwestern Loudoun County, near Harpers Ferry, West Virginia, and the Chesapeake Bay area of Virginia. The PHNST trail layer was completely updated for the PHNST 2022 Corridor Analysis study, which was conducted by NVRC in partnership with the National Park Service and Northern Virginia trail management stakeholders and was finalized and released in March 2023. Subsequent to the Corridor Analysis, the information is now updated continually as new information becomes available and at a minimum once a year. The trail GIS layer is incorporated into the PHNST Northern Virginia Dashboard, which is maintained by NVRC in partnership with the National Park Service. The Northern Virginia portion of the PHNSTs GIS information is the most authoritative data source for the trail and is incorporated into the National Park Service's maps subsequently, but their updates can have a significant time lag.The path or alignment that the existing PHNST follows was identified by PHNST management stakeholders and digitized using a combination of NPS and local trails GIS data. The planned, and proposed alignments are also designated in this layer and those alignments were obtained from the PHNST management stakeholders. Sections with unknown planned or proposed alignments are not designated. Information on maintenance status was solely obtained from the PHNST management stakeholders. This layer is meant to be used in conjunction with the PHNST Gaps GIS layer, for purposes of obtaining details on the planned and proposed segments, also known as gaps. Information on surface type, trail type, and trail width as well as walking, biking, and equestrian uses was obtained from existing local government GIS data, aerial photography, park websites, and information from PHNST management stakeholders. If the management stakeholder’s local knowledge and the existing GIS data on the trail differed, the management stakeholder’s local knowledge took precedence over existing data. Relevant jurisdiction GIS data sources and special studies are detailed below.Loudoun County: Existing trail alignment information was obtained from Loudoun County’s sidewalk and trails GIS. Loudoun County Parks and Recreation, the Town of Leesburg, and Northern Virginia Regional Park Authority staffs’ thorough knowledge of the trail were used to obtain surface type, trail type, and trail width as well as walking, biking, and equestrian use information. Local government GIS information on trail characteristics was not utilized. Planned trail alignment information was obtained from Loudoun County Parks and Recreation.Fairfax County: Trail alignment information was initially obtained from the NPS’s Potomac Heritage National Scenic Trail GIS layer from June 1, 2018. It was then modified using Fairfax County’s three GIS layers (all trails, sidewalks, and bicycle trails/shared-use paths). Trail characteristic information for all areas in Fairfax County where the PHNST is managed by the Fairfax County Park Authority and Fairfax County Department of Transportation were also obtained from these same Fairfax County GIS layers. Planned trail alignment information was obtained from Fairfax County management stakeholders..Trail characteristic information for area’s in Fairfax County managed by the NPS were obtained from the management stakeholder and the NPS’s Mount Vernon Trail (MVT) Corridor Study. To account for any trail improvements that have occurred since the MVT study was published in May 2020, the Fairfax County capital improvement project information was referenced.Arlington County: The NPS’s George Washington Memorial Parkway park, that of which includes the Mount Vernon Trail, covers the entire length of the PHNST through Arlington County. Trail alignment information was obtained from the NPS’s Potomac Heritage National Scenic Trail GIS layer from June 1, 2018 and spatially modified for accuracy as necessary. Trail characteristic information was not obtained from GIS information. Instead, trail characteristic information was obtained from the George Washington Memorial Parkway management stakeholder’s local knowledge and the Mount Vernon Trail (MVT) Corridor Study.City of Alexandria: The City’s walking GIS data and transit/bike lane route GIS data were the primary GIS data sources.Prince William County: Trail alignment information was initially obtained from the NPS’s Potomac Heritage National Scenic Trail GIS layer from June 1, 2018. It was then modified using Prince William County’s two GIS layers (trails and sidewalk centerlines). Trail characteristic information was obtained primarily from the Prince William County Department of Parks and Recreation's management stakeholders. In addition local aerial photography was utilized for trail characteristics. Planned trail alignment information was obtained from Prince William County Department of Parks and Recreation's management stakeholders.

Copyright Text: Northern Virginia Regional Commission

Min. Scale: 0

Max. Scale: 0

Default Visibility: false

Max Record Count: 2000

Supported query Formats: JSON, geoJSON, PBF

Use Standardized Queries: True

Extent:

Drawing Info:

HasZ: true

HasM: true

Has Attachments: false

Has Geometry Properties: true

HTML Popup Type: esriServerHTMLPopupTypeAsHTMLText

Object ID Field: OBJECTID

Unique ID Field:

Global ID Field:

Type ID Field: PHNST_Segment

Fields:
Types:

Is Data Versioned: false

Has Contingent Values: false

Supports Rollback On Failure Parameter: true

Last Edit Date: 2/9/2026 11:55:46 PM

Schema Last Edit Date: 2/9/2026 11:55:46 PM

Data Last Edit Date: 2/9/2026 11:55:46 PM

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