Have you seen Internet in a Box?
Very robust and fully developed, mostly geared towards EDU but it’s a Linux install. Mostly used on the Pi but anything you can put Linux on will work.
https://internet-in-a-box.org/
“Internet in a Box” means it’s basically a local server and other devices can connect via a browser.
27 minute video of description and install. https://www.youtube.com/watch?v=javfG88cZB0
Here’s a demo, en espanol - Mexico
Ok, well that post is a blast from the past! :) I think I have seen this a time or two in the past, thank you for bringing it up!
So I am guessing it is a mesh network then? Like Meshtastic? I have dove into the concept several times and we have a running thread over st the TA about it. The only draw back I can see is range without repeaters. I suppose it would be best for more populated areas where it can be relayed? Butthe Meshtastic is a similar idea I think, butit is designed to use add on radios that appear to give it pretty good range. And they use solar powered relay repeaters to make links at further distances.