Looking across Kilbrannan Sound from the former A843
The A843 was the original number of the road along the south of the Isle of Arran. Starting as a continuation of the A841 at Dippen, it ran along the south coast to Sliddery, from where it continued northwards up the west coast to meet the A842 to the east of Blackwaterfoot, with that road continuing into the village.
When the roads were originally classified in 1922, Arran was given three A-roads. For some reason, as shown on the right, the A841 and A843 formed a continuous route, changing at Dippen Farm where the road to Kildonan branches off. This strange state of affairs was rectified in the late 1920s, with the A841 being extended along the entire route of the A843 and ultimately on to make a full circuit of the island.
In the early 2000s the route of the A841 was curtailed and so the entire of the ex-A843 is unclassified.