The Brough of Birsay is the reason most travellers come this far round Mainland Orkney. A concrete causeway leads across at low tide to a grass-topped island with Pictish traces, Norse houses, a medieval church, and cliffs looking straight into the Atlantic.
It is a place to take slowly. Walk the ruins first, then continue towards the lighthouse and cliff edges, where puffins may nest in spring and early summer. The crossing is only safe around low water, so check tide times before leaving Kirkwall or Stromness.