We went the first time when ours was 3 months old and it was a nightmare LoL but I think everyone's different. Every situation is different. Just trial and error. If you feel comfortable, try it out! Just be ready to make a quick get away.
We’ve taken both our kids from a young age (6 weeks) I think and they’re used to it now. We’ve basically been monthly for the last 4 years.
We took our lo at 7 weeks. I dont think there's really an age as such it's just what you are comfortable with and the weather/time of year. We were in our van rather than a tent but it got pretty cold on the night. He was fine though.