For modern users, enthusiasts like Basic Apple Guy often host archives of these classic wallpapers updated for 5K and 6K resolutions. The Great macOS Wallpaper Bracket - Basic Apple Guy
If you are still running a legacy version of OS X, you can find the high-resolution system wallpapers in their default directory: Open and press Command+Shift+G . 3200x2000 OS X 10.8 Mountain Lion default wallp...
: It followed the design language of its predecessor, OS X 10.7 Lion (which also used a space theme), but refined the aesthetic to be cleaner and less visually distracting. How to Access Default Wallpapers For modern users, enthusiasts like Basic Apple Guy