|Distance:||1.9 miles (3.1 km)|
|Met (1934):||B865, unclassified|
|Now part of:||B9166|
|Route outline (key)|
Prior to the extension to John o Groats of the A9 in 1935, everything to the north of Inverness had been in the 8-zone. As such the road from Balintore on the Moray Firth inland to Fearn was the B866.
Following the change, the numbers of the B roads in the extended 9-zone were adjusted from B8xx to B91xx, so that the B866 (which found itself entirely on the eastern side of the new A9) became the B9166, which it remains.