B870 (Laxford Bridge - Thurso)

This article is about the former B870 along the north coast from Skiag Bridge to Thurso.
For the current B870 in Caithness, see B870.

The A836 (former B870) near Dounreay

The 1922 Road Lists list the B870 as originally following the coast around most of the north of Scotland. From the end of the A838 at Laxford Bridge it headed North East to Durness, then around Loch Eriboll and the Kyle of Tongue to meet the A836 at Tongue. From here it continued eastwards through Bettyhill and Melvich to the A88 (now A9) at Thurso.

The Barts map from 1930 shows the B870 extending southwards from its original route, across the Kylesku Ferry to reach the A837 at Skiag Bridge on the shores of Loch Assynt, thus extending this Class II road to well around 120 miles in length. However, this was short lived and by 1932 the original part of the route had been absorbed by eastward extensions to both the A838 and A836, while the southern section had been renumbered as the A894, with the B870 reallocated to its current route, wholly in Caithness. There have been many improvements to the Class I route since the B870 was reclassifed, one of the more notable being the causeway across the Kyle of Tongue.

The 1922 MOT Road List defines this route as: Laxford Bridge - Durness - Tongue - Thurso