While I don’t have a personal profile on Facebook, I do however use their events section quite regularly. It used to be very difficult to navigate but, recently, has become much more user friendly, allowing you to search events by their date, location and category, such as ‘art’, ‘gardening’ and ‘theatre’ to name but a few.
Events on Facebook are less likely to be free though, as they are generally set up by businesses trying to advertise their next class, workshop or big sale. Having said this, there are plenty of gatherings posted there that have no agenda other than to bring people together. I recently went to a free ‘Fire Meet‘ in Dublin where we all gathered one evening to watch some fantastic entertainers breathe, juggle and spin flames!