The Thakhek Loop is a 450-kilometre motorcycle circuit through Khammouane and Bolikhamxay provinces that takes 3–5 days to complete. Starting and ending in Thakhek, it heads east along Highway 12 (Cave Alley) through karst terrain, then north on Highway 1E, and back west on Highway 8, with a 42-kilometre detour to Kong Lor Cave as the centrepiece experience.
The Loop is done primarily by motorbike — semi-automatic bikes rent for about $10–15/day in Thakhek. The standard route passes through the cave systems of Route 12, the village of Tham Khoun for swimming, the Kong Lor cave area for an overnight, and the karst scenery of the Phu Hin Boun NPA. The return leg through Highway 8 and Highway 1E passes through forest and increasingly remote countryside before rejoining the Mekong valley. The loop can be ridden in either direction; counter-clockwise (east first) is most common as it reaches the main cave on day two while riders are fresh.