Anyway, I always wanted a red battlefield, if and when I did my own terrain but back when we were gaming as a group of mates our table was made of plywood and we had a big sheet of green felt. Cut to today and considering the large interest in Adeptus Mechanicus armies I found very few Mars/Red Planet terrain tutorials.
So my first option was to look at red felt which I was going to 'distress' a bit. This would have cost somewhere in the region of £15-£20 and although I've since looked at a couple of alternatives GW's own Realm of Battle Gameboard [tooexpensive], Zuzzy Miniatures awesome looking Terra-Flex System battle mats [a third the price of a gameboard, easy stowage but not as versatile], a big sheet of B&Q insulation foam carved up and ready to game [V.cheap but hard work to make and a pain to store without damage], I opted for the cheapest option available to me - a big laminated print out of aerial photography!
Of course you need access to a large scale printer and laminator for this sort of thing and if you even look at high street printers who offer such a service you're better off with the felt route, or even the B&Q foam route if you have the skills to model such a board and store it. However if you can access such things here's a copy of my red planet battlefield to print out. It'll easily cover 4'x2' at 144dpi so you could blow it up to do a 6'x3' with only a little loss in quality. It's just over 2MB if you're worried about filesizes.