Where might a detour lead? It is a question often pondered when travelling by car and the bright orange signs announce detour ahead.
Follow the signs. Sometimes it is only a narrow work-around that has been created for this one project. Sometimes the next sign indicates the road narrowing to a single lane and stop lights tell you when you can travel.
Sometimes after stopping, you are led through a working area by a guide truck leading a parade of 20 or more trucks and cars.