The B8017, like its neighbour the B8018, is a strange road winding around the northern end of the Rhinns of Islay. Neither of them really go anywhere or serve any villages, and so why these two routes were picked out as worthy of being B class roads over the numerous other, similar, routes on Islay is a bit of a mystery. These roads were originally unclassified but had gained their numbers by 1932.
The B8017 starts at a sharp fork from the A847 just west if Blackrock (a mere scattering of roadside houses). It then runs north west, turning north at the farm at Lyrabus, where a track (it can hardly be called a road, despite occasionally being marked as such) turns off to the left, back to the A847. A mile to the north, the road swings sharp left, with a right turn again leading back to the A847, this time near Bridgend. Soon after, another right turn is a long dead end heading north up the eastern side of Loch Gruinart, a large sandy estuary area cutting deep into the north coast of Islay.
After a short drive past the scattered houses and farms of Gruinart, there is another right turn which leads up the west coast of the loch; again it is a dead end. The B8017 then continues vaguely westwards for another 2 miles across the relatively flat farmland that is found in the part of the island, terminating at a simple T junction with the B8018 above Loch Gorm. There is no name for this junction, there is no building particularly close, and different maps label different nearby 'settlements'.