At Tarbet, the A83 branches west to Campbeltown while the A82 continues to the north end of the loch. This part of the road is currently of a lower standard than the sections further south. It is sandwiched between the shoreline of the loch and the mountains to the west, and it runs generally alongside the West Highland Line. The road narrows to less than in places and causes significant problems for heavy goods vehicles (HGVs), which have to negotiate tight bends and the narrow carriageway width. At Pulpit rock, the road was single-track, with traffic flow controlled by traffic lights for over 30 years. The road was widened in 2015 as part of a £9 million improvement programme, including a new viaduct bringing the carriageway width to modern standards.