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What types of maps do you have available?
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TerraServer maintains a database of topographic maps and aeronautical charts that display in the Image Viewer. We are looking to add nautical charts in the future.
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What is a topographic map?
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Topographic maps supply a general image of the earth's surface: roads, rivers, buildings, the relief (the elevation or depression), and the names of the various mapped objects. Topographic maps are most often characterized by the contour lines. Contour lines are lines drawn between points with the same elevation. Because the Earth’s surface is continuous, all contour lines are continuous and do not have an end.
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What is an aeronautical chart?
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An aeronautical chart displays the coverage area of aviation radio towers and air traffic control towers. They also display restricted airspace areas as well as flight impediments, such as tall buildings.
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Is a topographic map or satellite image better for my needs?
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Topographic maps are useful when the ground features are important to your project. They show water features and the contour lines illustrate the gradient of the surface in question. If the vegetation coverage or anything above the surface is important to your project, then you may be better suited by an aerial image.
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Are topographic maps available for my location?
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Topographic maps are available for the entire United States. We do not have them available for the rest of the world.
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What do the lines on a topographic map indicate?
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The lines on a topographic map are called contour lines. Contour lines connect points with the same elevation. If you were to move along a contour line, you would never change elevation. By moving perpendicular to the contour lines, you would either be walking up or down hill.
For example, a mountain would be characterized by a very large circle at its base with continually smaller circles as you moved towards the center. The peak of the mountain would be shown by a very small circle.
Because the Earth is continuous, all contour lines will be continuous and not have an end point. Contour intervals very over different maps and can be determined by looking at the reference contour lines and then counting the number of lines in between.
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Why are the topographic maps so old?
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Topographic maps tend to be older because the geographic changes of the Earth tend to be minimal over any sort of measurable time with the exception of natural disasters. Because of this and the intense amount of work required to develop topographic maps, they only tend to be updated whenever necessary.
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Can I get a legend to better understand my topographic map?
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Do you have nautical charts available?
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Currently we do not have nautical charts available, but we are looking to make them available in the near future.
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