Static Map Legend

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A viewshed map shows the terrain a camera can see, drawn over the landscape around it. The legend below lists every symbol used on those maps: the camera and its visible area, roads, water, boundaries, protected land, and named places and landmarks.

This legend covers the static map sheets only.

Want to learn more about how our viewshed maps are created? Read the viewshed methodology.

The camera and its view

On every map in the set.

Visible area

Ground in direct line of sight from the camera.

Camera

The camera's position. Where the marker is a wedge, it also shows which way the camera faces.

Field of view

The span the camera is aimed across, drawn from its bearing and lens angle.

Range rings

Distance from the camera, at intervals named on the map.

Roads

Drawn on maps whose scale can carry them; the widest maps show only the largest classes.

Interstate highway

A controlled-access divided highway for through traffic.Classification: Federal Highway Administration functional class

Highway and major road

Hard-surfaced routes connecting principal towns and linking them to the primary highway system.Classification: Federal Highway Administration functional class

Water

Shown where the mapped area contains it.

Lake, reservoir and bay

Standing water large enough to draw as an area at this scale.

River and stream

A named watercourse. The closer maps carry smaller ones; the wider maps keep only the larger.

Boundaries

Administrative lines, drawn where they fall inside the map.

State boundary

The line between states. Not a barrier to the view — shown because it helps locate everything else.

Protected land

Shown where the mapped area contains it.

National and state park

Land in public protected ownership, from the USGS Protected Areas Database.Classification: USGS Protected Areas Database of the United States

Places and landmarks

Named features, limited by how many will fit legibly.

City

Larger settlements, carried across the wider scales.

Town and settlement

Smaller places, shown on the closer maps.

Summit

A named summit. Which ones appear depends on the scale, on how prominent they are, and on whether they fall inside the visible area.

Named landform

Ridges, valleys, passes and similar named ground.

What these maps do not show

Individual buildings, property lines and land ownership other than protected public land.
Contours or spot elevations. The maps show what can be seen from the camera, not the height of the ground under it.
Vegetation, except where a camera is analysed with screening — and even then it affects the visible area rather than being drawn as a layer.
Every named feature in the area. Each map carries as many labels as it can show legibly, chosen by prominence and by whether the feature falls in the camera's view.

Sources: Elevation USGS 3DEP · Hydrography NHDPlus HR · Roads & Boundaries US Census TIGER · Places & Peaks USGS GNIS · Protected Areas PAD-US