A really beautiful image- I especially like the clouds (I'm a big cloud fan and have a future rant planned about them). Is that a photo, or? Yes, splitting the DEM's into three sections is ideal for doing Eco-Systems. My thoughts exactly! Could you imagine a 8K x 8K Eco-Terrain with 81 Billion Fir Trees? (Well- after 64 bit Windows finally comes out and gets debugged- and "Vue 7 Beyond Infinity" comes out, we will probably see it!) Again- beautiful- excellent lighting and terrain materials are really great.