They are closed right now due to people abusing the lake. It is first come first serve. If you are looking to get a site for the weekend it's best to show up Wednesday or early Thursday.
Staircase campgrounds are first come first serve. As long as a space is available. If there is, you are supposed to leave something at the site to show it's taken, then there is a board at the campsites entrance to mark and pay for the spot.
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