Hi There!!
This is an Island Terrain and its dimensions are 8000x8000x2600 meters or 8x8x2.6km. there are total 25 files, which in includes: 15+ mask like flow, vegetation, water, beach, soil, slope etc. 3 different height maps, one with fake foliage in tif, other two are normal heights in tif and r32(raw) formats and all are 32 bit maps. some other useful maps like details, world normal, and texture.
Demo blend file included, with tree cards and demo render setup. you can just mask as assets the terrain in given blend file and put it in you asset library, demo blend file is only couple of MBs due to procedural workflow of mine.
triangulated fbx mesh included in around 4 million polygons (adaptive).
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