BuddyPress.org

Cool idea. It sounds like BP is a good fit, with BP groups used as towns.

Some places to start:
– Change the word ‘group’ to ‘town’ throughout BP text and URLs: https://codex.buddypress.org/extending-buddypress/customizing-labels-messages-and-urls/
– Setting up group forums: https://codex.buddypress.org/buddypress-site-administration/buddypress-forum/ (see the bottom section)
– EventPress, a BP plugin for events: https://wordpress.org/extend/plugins/eventpress/

Good luck!