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.
Draak Noir, sergioregofic, ARVN- 1st Infantry Div, Sssss, gamingthewindows, bjv, nawapon.j50, l.alexis40465, romyc1984a, sebasmoutt, orco12354, notme18938, gustavogabrielrc, boniebest10, blankname401, iceprofi21, samandarvish84, alguienraro2221, ItsGoldPlays, leonardofabiomartinezmu01, leonardofabiomartinezmu01, Chris, Gr3y.H4wk, krolikowskistanislaw0, Edward Meise, ʳᵃᵍᵍᵉᵗˢ, CARLITOS NOPE F2P YT, ·xX+ºLu_Alphaº+Xx·, dmitrijurevic428, whoisrokon, Пылесос Electrolux, Systane, westht, giovanni.galdeano.argentina, kornilovairina.86, The Butter Man, noodnofree, 素晴らしい人生, irfangreatman3, [USF] Stickman Gunderson, FoxisGamer12, thefinesttim, OK2, neozero10, paciorka1, Dylan T, You're Aren't, You're Aren't, You're Aren't, henrryrond123o +1632 others
