This might veer around a bit 
We went to our first swingers night last week. A newbie event which we made the most of. We don’t want anyone else involved (though we are pursuing a common fantasy involving a third as a one-off, but that’s another story entirely!), but love to see and be seen.
The club was good and we showed ourselves, but not really our scene. We talked about going back so we could be in a room full of people having sex, (you could almost taste the collective hormones at one point at the club) but not be involved with others, but we’re a bit hmmm
We see ourselves as Mother Earth’s children; green and a bit pagan. We’d love to be around a campfire in the woods at night with a crowd, all of us at it with partners- monogamous group sex, I guess- but can’t find anything out there on fetlife or fab
Are we just being too niche, or can anyone point us in the right direction?
Maybe I’m being relatively naive, but if you can’t find what you’re looking for then you could maybe arrange something yourself eg with the people you meet at these events/fetlife etc.
All that I would say, without trying to deter you, is that you’d have to put a lot of consideration into how you may vet people to ensure you’re with those you trust and are safe etc.
Agreed. I was hoping such an event might already exist that we just hadn’t been able to find. As for a community for a new event, I’d start here, you are a grand bunch
We’ve been to swingers clubs that have orgy rooms. The rooms are open and offer a larger area than most rooms where 10 or so couples could play. People in these rooms may be ‘swinging’ or just having sex with their partner. Although labelled an orgy room people still show the same respect that they would normally do at a club of this kind. They may ask to join in (rare) or play with others if invited but would never touch or attempt to initiate play otherwise. Our experience of these rooms has been that people enter the room as a group if they want a ‘group’ expedience but couples that enjoy playing alongside others will also be present. While not the camp fire experience you crave I think it’s very easy to have a monogamous experience as a couple in one of these rooms.
Don’t forget the most important part of it being a full moon too! Something about having sex under a glowing moon in its fullest that heightens things and the energies 
We don’t do clubs just not for us in our view but we would a 3rd so totally understand so we trying to do our own thing and see if we can agree x
Unless somebody else comes up with an easier solution, it sounds like you will have to DIY.
A few years ago, we had a few trips to swinging venues, just to watch, be watched and enjoy the erotic atmosphere. Like you, we had no intention of playing with others. Some of these visits were with like-minded couples (one couple at a time) that we had linked up with via swinging websites. It was pretty easy to locate couples who were on our wavelength, and to assess them through a few online chats, before agreeing to meet.
For convenience, we arranged to meet them at swingers’ venues, but it’s not necessary. You could just reserve some accommodation and share the cost. There are plenty of self-contained/secluded places you could hire.
We wish you luck. It sounds like you will have a fantastic experience.