@Edent I think that for adding a geo coordinates context to a generic ActivityPub object, the location property is probably what you need. But probably there are no clients that would know how to interpret it at this time.

@cwebber

Pixelfed shows locations. I might see them if I'm looking for them.

Of course, I might also be the guy to add "location": {"type":"Place","name":"The end of the rainbow"} just to see if someone calls me out on it.