How can Bengaluru build its way out of traffic?

Bengaluru’s proposed tunnel road has brought an old question back into focus: can the city actually build its way out of its traffic mess? The answer is unlikely to come from one mega project. Tunnels, flyovers and wider roads can ease congestion on particular stretches, but the relief may not last if the number of vehicles keeps climbing. What Bengaluru needs is a transport system that makes it easier for people to leave their cars at home, while also making better use of the roads it already has.The tunnel roadThe attraction of a tunnel road is easy to understand. It can take traffic below some of the city's busiest roads, bypass crowded junctions and create a new route without requiring large-scale land acquisition on the surface.But there is a catch. Traffic does not end when a tunnel ends.