Kiwix Server is a .zim compatible web server: it allows you to deliver .zim files over the HTTP protocol within your local network. Simply start the server on your machine, and your content will be available for anybody through their web browser.
ZIM files can be downloaded here: https://wiki.kiwix.org/wiki/Content

        Expects ZIM files to be stored in the ZIM Data Path. Can be downloaded from https://wiki.kiwix.org/wiki/Content