I guess Wild Camping has two sides to it:
The first is spots that are not easily accessible to normal vehicles or places hidden away from roads (Jed style spots)

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The other are spots that are not campsites or officially marked camping spots (not that you get any on this island), these could be lay-bys, car parks, picnic spots, quiet country lanes or tracks in quiet locations (fire roads or similar in wooded areas), not to forget the standard parking bay on normal roads (used them a few times).