You can get a reservation online but the site choices are first come. Some are totally miserable with no shade but others have some nice shade. We went to the onsite cafe wToo many times-pancake breakfast was awesome. When we went, it was during the big 416 fire so there was a fire ban but propane was okay. The bathrooms and showers were pretty good. There is also a laundry area. They are very strict about keeping anything that may attract bears in your car. The roads are good but are winding roads in the mountains. There are lots of different trails to check out as well as cliff dwellings-some require tour tickets. 

Went in June