This download looks like a map. You need to place it in your maps folder inside the Garry's Mod folder.
You should end up with a directory structure similar to below
Don't know where the Garry's Mod folder is or how to extract zip files? See more useful installation tips.
red_impostor, apagamer10, masascuate666, alexismarzano54, enrico.duque123, bialyk436, bialyk436, Halo990864, kaos, combine 049, combine 049, kd6864827, mhmid097, VojnikSrbije, kazanilanodul, superspy, JeyCeab, , A-l, XxPiotrek577xX, KermitTheFragGrenade, milosevicslobodan2231, допрыгался TкофеT, bakiev2006, keaw0877654436, Communist Vietnam ☭, THAI EMPIRE, 2068721148, Ds.Mancilla_14, keawlovepig, qqqtrs, 295222507, hochat12, sergiokanekidead, aether_sky, ultima_sword, vladutsarca112, lights18, prarinjub, berkesarpda4, aliqar, gmangp1453, xbreshanaj6, minhtringuyendinh, erdemlioyuncu07, Towelie, kk2446194, 89514977065, florin21pruna, acetaminophen addict +90 others
