you are just an idiot and don't know how to find it

This is for anyone that can't or cannot find the file. go to your C:\drive or your main Garry's Mod drive/ steam storage area, then if you are on windows you should see a search box type this in 2010286798. You should find a temp.GMA file that is the map. It is saved differently because of the size that the map is. Or you could just use {LENKE FJERNET}https://steamworkshopdownloader.io/ this website to download the map, not hard to do a little bit of research before you complain!

Thanks for introducing a method most people who look up "cant find gma or bsp file on the internet" don't know, appreciated

EDIT: 2010286798 isn't a thing in my files at all.

it's not going to be in your Garry's Mod files. It will be in your steam Directory! so just go to your C:\Drive and search for it. If that doesn't work, just use the website to download it.

i am confusion

All addons that have been uploaded to GMod's workshop after the January GMod workshop update, will be located in pathtoyoursteamfolder\steamapps\workshop\content\4000, instead of your addons folder. Folders are named after workshop ID's, so copy this workshop page's url and look at the numbers after " id= ". RP_SouthSide's ID is 2010286798, so that's the folder you're looking for.