Thread:Talk:Semantic Maps/map including all posts from certain category

I am building a wiki based on a specific territory... and I would like to have one function on the homepage: a map of this Territory showing only one (or more) categories of pages that include a map themselves. I have created a few pages that include a map, like for instance this one: - and they're good on their own.

But now I would have to create a map that shows all pointers from a certain category, and even more than one. How can I do this? I've read quite a lot of documentation, but couldn't find any useful info about this. My aim is to make things "discoverable" via a map... someone must have done this already, but I could not find any useful info so far. Help! :)