As the Boris Johnson administration drew to a close, one government department that didn’t get the memo to down tools was the Department for Transport. In August, the DfT announced a £100m funding boost for what it called a “self-driving revolution”, setting Britain on a course towards a future where autonomous cars, coaches and lorries could be running on our roads from as early as 2025.

It’s simultaneously a bold new step and utterly uncontroversial, as whoever is living in Downing Street is going to have to deal with the reality that autonomous vehicles (AVs) are coming.

However, what’s important about AVs is not just what Tesla, Google, and maybe even Apple are up to. What’s going to be just as critical is the road network on which the ‘revolution’ takes place. So just how are AVs going to change our roads?

“That’s the fundamental question that keeps me up at night,” laughs Andy Fisher, the Connected and Autonomous Vehicles team leader at National...