Between them, the M50, A40 and A449 form a single dual carriageway route connecting the West Midlands to South Wales, incorproating one of the UK's oldest and most scenic motorways.
The A465 Heads of the Valleys Road is one of the most spectacular trunk roads in the UK, and building it required some of the most remarkable civil engineering. This is the story of how the road was built in the 1960s, and how it's being rebuilt today.