|Length:||5.1 miles (8.2 km)|
|Route outline (key)|
The B864 is a short link up the west side of the River Shin in south Sutherland. The road was originally unclassified but had gained its present number by 1932.
As the road parallels the A836 on the east side of the river, it seems almost superfluous. However, it does provide access to the car park for the Falls of Shin, a picturesque series of low falls and rapids towards the southern end of the route. The road itself is all single-track, winding along between passing places and often under a dense tree canopy giving it a very un-Scottish feel! North of the falls, the scattered settlement of Achany is passed through, and then after a couple of minor junctions the road suddenly opens out to meet the A839 just to the south of Lairg.