This is a community map for L4D2, made by myself in Hammer. I had 14 days to make it and had very little previous knowledge of the engine, going into it. I am pleased with how it turned out, but if I were to go back and change anything, I think I would try to add even more elevation to the map, as it is quite flat as it stands.
http://steamcommunity.com/sharedfiles/filedetails/?id=266517979