The Pagan Federation is the major UK representative body for Pagans of all denominations. In London they hold celebrations at Conway Hall, Red Lion Square, around all of the eight seasonal festivals, and have a social called Pan’s Picnic every year. The organisation in London is very friendly, if a bit wacky and wonderful, and any attendees should feel totally safe and welcome at all events. The events are completely accessible to anyone, even if they don’t have the faintest idea what the deal is with the whole Paganism thing. I do suggest going along to the event and taking in the convivial atmosphere and of course the mead.