The yellowish-green grass area is underlain by dunes formed of shell-sand blown in from the beach by the persistent westerlies, the brighter green is land cropped by generations of crofters' sheep.
Hebridean Air Services who fly from Oban to Coll, Tiree and Colonsay, so it can't be one of their scheduled services, so it must be a charter - or lost.
This is the first time we've taken a serious walk in the hills since returning from holiday in Canada and, by the time we returned to the car after three hours of heavy going, our legs were complaining. But we weren't. Grey as it may have been, a walk around Sanna is always a pleasure.
There's a map of the area here.