Quantum GIS (QGIS)

QGIS is strikingly similar to ArcGIS and is without a doubt the #1 free GIS software package available. From automating map production, processing geospatial data and creating stunning cartographic figures, QGIS is jam-packed with a plethora of powerful tools.

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Whitebox GAT

Whitebox Geospatial Analysis Toolbox is another open-source GIS and remote-sensing software package packed with over 410 tools to clip, convert, analyze, buffer, manage and extract geospatial information.

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