The right of way seems to be based on the size of the vehicle (cars win over bikes) and in order to reduce the number of collisions drivers honk every time they turn, pass another vehicle, want more space, or just feel like it. My ears really had to get used to this level of noise, really stressful sometimes. Especially in the first days I had the feeling of constantly being in danger of getting run over by a bike. The sidewalks of Hanoi are mostly occupied by parked motorbikes. Hence, as a pedestrian, one has to share the edge of the road with hurrying motorbikes (and here you can’t rely on them driving on the right side of the street). Walking along a street is already adventurous, crossing a street seems almost impossible at first. There are no or only short gaps in the stream of bikes and cars and traffic lights are rather an exception. The secret here is to just move very slowly and give the approaching bikes enough time to consider you and drive around you. Crossing bigger streets can well take more than 30 seconds and the first times strolling just in the middle of hundreds of motorbikes during rush hour seemed like madness. After some time I got used to it, though.