This Spot has the most high leveled zombies ive found on this map
First off go to this Spot its on the right side of map near Faymoor


There will be a barricade hop on it, thats the spot where you taking the zombies out


after you found that barricade you'll just have to get into Hordemode and hop up there
but be aware they CAN deal high damage

Did you kill all of them and want more ?
simply reload the map


This might also be helpfull