The death_valley_10_170809_2090.zip file you have requested: Maps Levels Missions / Survival Maps / Left 4 Dead Survival Map Death Valley - 2.6mb is not available. Perhaps try browsing all files for the game Left 4 Dead and upload any files you want to share or are missing. This is the only information we could locate:
Death Valley is a fun survival map, where you hold off in a 4 story fort that has miniguns, barricades and a front door. This map has been tested and there are no glitches/errors(That I know of).