Installed in 1994, the lights are used once a year to demonstrate how red-yellow-blue (the Japanese call the green light blue) lights work. The primary school in Himakajima escorts its third and fifth graders down to the port to practice crossing the street with a real traffic signal. Children line up at the signal, wait for it to change, look both ways, and cross within the "zebra stripe" crosswalk with their arms raised to help with visibility. In this way, they learn city traffic etiquette and proper procedure.