This is a creative way of generating a 'melody' by simply driving your car over a grooved stretch of road at the correct speed.
The 'melody road', can be seen above and the grooves are between 6 and 12mm apart: the narrower the interval, the higher the pitch. These stretches of road, each playing a different tune, can currently be found in 3 places in Japan - Hokkaido, Wakayama and Gunma - with the optimum musical speed being a depressingly slow 28mph.
