The 37-year-old star said it was a great experience and the time they spent together after the shoot contributed a lot to the film.
"He (Ritchie) does have an exceptionally cozy trailer. It's very difficult to get him out once he's got the log fire going and some eggs cooking on the stove. Guy creates this dynamic wherever he goes.
"The camping was wonderful. I'd always dreamed about what it would be like to just live around a film set and not be taken out of it. This was that experience for a brief period of time. We were in Wales for three weeks, but we all lived together in these little caravans by a lake," Hunnam said in a statement.
"It was a lovely way to make a film," Hunnam added.
"King Arthur: Legend Of The Sword" will hit the theatres this Friday.