Derived from elevation grid. Data available from the United States Department of Agriculture Forest Service.

Grid from Digital Elevation Model, based on USGS 15" quad 100 foot contour lines. Data available from the United States Department of Agriculture Forest Service.

100 ft contour lines for the Chugach National Forest, digitized from USGS 1:63,360 quads. Data available from the United States Department of Agriculture Forest Service.