The two humps on the horizon are the Red Hills by Broadford in Skye, as I said, 75 miles to the south of Stornoway. This picture was taken on 10 February, when visibility was very good. You can see from Cape Wrath all the way down to Kyle of Lochalsh; Cape Wrath is visible at night particularly on account of the lighthouse, whose flashes can be discerned from just below the horizon as you stand near the Butt of Lewis. The mountains on the mainland stand out at this time of year, wreathed in snow.
From my own viewpoint in Stornoway, I can make out the hills around Applecross on a clear day (like this afternoon), a mere 60 miles to the southeast.