CADMAPPER - Instant CAD files for any location on earth
FreeCAD - An open-source parametric 3D modeler
MAPACAD - MAPACAD is an online website that is providing leverage to designers and architectures to have the ability to download CAD map cities that can be directly used in their projects.
LibreCAD - An open source 2D CAD application for Windows, Apple and Linux.
Cadbull - Cadbull is a website that comes with an advanced collection of CAD blocks and DWG design, facilitating architects and designers to get done with their projects efficiently.
SketchUp - 3D for Everyone