Colin D.
Yelp
Cool island only reachable at low-tied with some ~1000-year-old ruins and a lighthouse. Fun, but not the most amazing example of any of the three.
So, the coolest part about this is that it's kind of a magic island that you can only get to for about an hour either side of low tide. That's just really cool and appeals to kids especially. It's basically a secret island.
Beyond that, there's some ruins of a church and settlements that go back, but they are far from the most interesting such ruins on Orkney. There's also a cool old lighthouse, but again, probably not the coolest lighthouse and you can't go in or tour it. Lastly there's some sea cliffs and rugged Scottish coast, but again not the best you can find--even on Orkney. You can combine it with a visit to the tea room (which has a view of the Borough) and wander around the Earl's palace ruins, which make it a more full outing, but the key thing is whether you like the idea of a secret island you can only reach a low tide or not.