Believe me it's hard and takes time. The design process starts with paper and pencils. AutoCAD Civil 3D is used for the analysis and etc. 2D drawing is prepared with AutoCAD, some small buildings (cafes, WCs etc.) and some undetailed parts modelled with AutoCAD 3D, terrain modelled with AutoCAD Civil 3D. All the other modelling (vegetation, mapping, lighting and etc.) done in 3Ds Max Design and rendered there with mentalray. At the end Photoshop comes to scene for post works.

Even I mostly myself did the viz. process, it's a team work. This work took nearly one month, after the design process. As I can see from your gallery you can do it too. It's just a matter of starting (from wherever u want)

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.:: bearsign ::.