Data Sources How to Download USGS Topo Maps for Free If you’re looking for topographic maps (contours, place names & hydrography) for the United States, the first place to look is the USGS topo maps series.
GIS Analysis Append Tool in GIS The Append Tool adds data from one or more sources of data and puts it into an existing target dataset, without creating a new dataset.
GIS Career Geodesy: The Mathematics of “Where” Geodesy is the field of applied mathematics that studies Earth’s shape, orientation, positions and gravity for the past, present and future.