I visited in November, on the first days of rain after a long dry season. I arrived after dark and was unfamiliar with the layout, so I stayed at a pull-out near the McCabe Flat campground. The next morning I checked out Willow Placer campground and continued to the end of the road to claim the last spot at Railroad Flat campground.
All three camps are along the river. There are no reservations. The first two are mostly walk-in tent sites. They are all clean and well maintained. There was a helpful ranger on patrol through the weekend.
I came with my 16’ Airstream in tow, and it fit perfectly. I would not recommend anything larger. It was late in the season, so there were only a few campers at each location. The narrow road winds along the steep canyon wall with occasional pull-outs to allow oncoming cars to pass. I was glad not to meet any vehicles on my way.
The scenery was stunning! It rained on-and-off with sunshine in between, so I rode my bike along and went fishing (didn't catch anything) while the sky was blue, then hid under a blanket with a cup of tea and watched the stormy skies. I had initially planned to go to Yosemite but was content to stay here.