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.
alexecheverria429, R(ed), Tyrannotitan Fan, VilTheGreat, NatasateThailand, niceloma, TechEmpire2684, samurai_&_kiwi, BokMustang, Bonelord, Xeonas, joaopedro_sf, skirmYAR, JOAKIM CURURU, CelDamage, nahuel0612, Jimmy Casket, dinovan, vector343mariobros, Lasers, QuinCraftables, ASTRO_119, Xanadu the Dominator, Greatestgamertolive6, skull037, flight6t6, jaiuyet, jon142010, quintjawsman, Chudman, Cirno Scarlet, BigWAT, Wolfie The Wolf, MireTSBS trade.tf, truskiek1, truskiek1, Draluigi, Yusuf Kahveci, spaecii, MaRcALleN990, tedted21, Retarded Mario, 1uk, somebody in red suit, Godzilla 2019, Mado Kureo, иоcтёdоцт, aardappelsalade, aardappelsalade, Albert Softie +6 others
