The old Roman Road sort of forks right here onto the B8049
The Military Way is the modern name for the Roman Road that ran along the southern flank of the Antonine Wall, connecting the forts together, and extending roughly from Old Kilpatrick on the Clyde to Bo'ness on the Forth.
Almost no evidence survives on the ground for its existence - remains of the wall are few enough - however, the A808 and a short section of the B8049 are named 'Roman Road', and there is sufficient evidence to believe that they do follow the Roman route, showing that at least half a mile has been preserved as a road for 2 millennia. However, the junction between these two classified roads is almost certainly not on the old Roman Road, as it has been slightly realigned to fit around the railway line that the B8049 immediately crosses.