I will use xv to the day I die. Great for remotely viewing / editing images (e.g. headless EC2 instances). Has features I can't even find in a modern image editor. http://www.trilon.com/xv/
You can also try feh (https://feh.finalrewind.org/) feh is an X11 image viewer aimed mostly at console users. And sxiv (https://github.com/muennich/sxiv) Simple X Image Viewer (but this one was archived on github since Nov. 9th, 2022) and now replaced with nsxiv (https://github.com/nsxiv/nsxiv) Neo (or New or Not) Simple (or Small or Suckless) X Image Viewer.