After the Royal Oak was sunk in Scapa Flow, Churchill ordered barriers built between some of the islands to make the fleet anchorage more defencible.
The island of Burray is between barriers three and four and from the top of the hill is the only place that all four barriers can be seen at once.
The sky in this panorama looks odd. That is because it was a windy day and the clouds moved so much in the few minutes it took me to take all the pictures that I can either make the clouds look right and the blue of the sky is patchy or the overall blue is good but the clouds look wrong. I decided to go for the latter option.