...the sea around the Outer Hebrides really is this colour:
That's the view over to Taransay, an island off the west coast of Harris.
Taransay is most well-known for being the location for Castaway, a show from the turn of the decade when 30+ people were dropped in, with buildings and various supplies, to see what kind of community they could form during a year.
A few of the buildings remain on the island, and there is also a "pod" house that has been relocated to the Luskentyre road.
The picture is from the excellent Flickr photoset by diamond geezer.