|Location Map ( geo)|
|To:||St Colmac (NS055672)|
|Distance:||3.2 miles (5.1 km)|
|Now part of:||A844|
|Route outline (key)|
The B879 is described in the 1922 Road Lists as Ballanlay - Kames Castle, making it a short road on the west coast of the Isle of Bute. As such it was essentially a northwards extension of the B878 (which at that time ended further west than it does now), heading north to Ettrick Bay before turning inland as far as the B877 at a point between St Colmac and Kames Castle.
In the late 1920s it became part of an extended A844, as did the two roads it met at either end.