I agree with the answers. It's popular and its already mid-June. 50/50 chance you'll get a weekday spot. Not a good chance you'll get a weekend spot w/o a reservation.
We did as well make reservations
There are both walk up and reservable sites. You can make reservations up to 6 months in advance at recreation.gov.. It is a very popular campground that both reservation and walk up usually fill up during the weekend. You can usually get a spot on Friday or any weekday.
We did for a weekend visit. Weekdays you might not need reservations.
No, I didn't when I went. although some can be reserved I think. I think they have spots that are only first come first serve but am not certain. You might want to verify on their web site and try to make it there early to get those first come first serve spots.
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