When we were ready to leave St Kilda, our boat took us on a jaunt around the bottom of Boreray, Stac Lee and Stac an Armin.
They are huge chunks of rock rearing straight out of the sea, and towered above our tiny wee boat.
Almost every available ledge on Stac an Armin seemed to have a gannet sitting on it.
Boreray was the only stack that seemed to have any colour: