Contourlinien

ContourLinien are lines on a map that connect points of equal elevation, depth, or occasionally other physical values. In cartography, they are commonly referred to as contour lines, and ContourLinien is the term used in German-language maps. Their primary purpose is to convey the shape of the terrain in two dimensions, allowing readers to infer mountains, valleys, ridges, and depressions without a three‑dimensional view.

The spacing and labeling of ContourLinien convey relief and slope. Closely spaced lines indicate steep terrain, while widely spaced lines show gentle slopes. Index contours, typically darker and labeled with their elevation, help users read the map quickly, with lighter intermediate contours filling in the detail. The choice of contour interval—the difference in elevation between adjacent lines—depends on the map’s scale and intended use.

ContourLinien are created from elevation data, most commonly digital elevation models (DEMs) or LiDAR surveys. Geographic information systems (GIS) generate contours by interpolating elevation values at regular intervals. The resulting lines can be rendered as vector data or converted into raster formats, and may be generalized for readability at smaller scales. In addition to elevation, contour techniques can represent depth below sea level or other continuous variables, though elevation is by far the most common application.

Applications of ContourLinien span topographic mapping, urban planning, environmental assessment, hydrology, and outdoor recreation. They aid in route planning, flood risk analysis, land use decisions, and landscape visualization. Limitations include dependence on data accuracy and resolution, potential clutter in densely featured areas, and the need for appropriate generalization at different map scales.