Did this today- well, i'm currently camping along it at the moment,- was recommended by a ranger as a less crowded trail, and that was the case today, but still saw 4-8 folks. Crossing the stream at Big Rock Falls before the Rapidan Camp was a little perilous with some distance between river rocks - I'm a long-legged 6'0 and I had to jump a bit to avoid getting a wet foot. I would NOT recommend this trail if heavy rainfall was recent. History buffs may be interested in Rapidan - it's a little mountain lodge that Herbert Hoover had made in the late 1920s (most buildings are no longer standing). Nice unmarked camp areas along the creek shortly after Fork Mountain trail branches off this loop - but had some difficulty finding a decent bear bag branch