Soldiers at Edinburgh Castle

This evening, I went on another Wander round the Old Town with my camera. I decided to go to the Castle Esplanade to see if I could get a nice sunset picture, but there were military police stopping anyone going ono the esplanade. A few minutes later, this group of immaculately uniformed soldiers marched out of the main castle door and left by the stairs down to Johnston Terrace. Anyone know who they are?

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