GTTV stands for Grand Theft Tekkit V. In GTTV there is Liberty City, like GTAIV but with the vehicles of GTAV. This is a Tekkit map with the mod pack Iconic War. You must have this war pack on the Technic Launcher before downloading this map. You can get the Technic Launcher (Tekkit) here. After you have this launcher, extract it and open it up. Press add new pack. It will ask you to paste a link in. Paste this exact link: www.technicpack.net/api/modpack/ionicwar
Then click Add Modpack. After you have it added click on the Iconic War icon and enter your Minecraft username and password. (Don't worry this isn't a scam thousands use Technic Launcher) It will take 3-5 minutes to launch the pack but then you have the pack. Now you download this map into the Technic Launcher saves. (Located in Roaming>.tenchniclauncher>saves)
Please note that I cannot post the map right now because PMC no longer allows mediafire and I am looking for a Non-survey downloader.
Hope you enjoy!