It’s a painting called “Valley of the Dead” by the surrealist Polish painter Zdzisław Beksiński.
Other examples of his work
https://c4.wallpaperflare.com/wallpaper/863/334/362/zdzisław-beksiński-dark-wallpaper-preview.jpg
https://c4.wallpaperflare.com/wallpaper/202/426/400/zdzisław-beksiński-wallpaper-preview.jpg